The structural feature shown on a remote sensing image is a synthetic result ofcombination of the deformations produced during the entire geological history of an area.Therefore, the respective tectonic stress field o...The structural feature shown on a remote sensing image is a synthetic result ofcombination of the deformations produced during the entire geological history of an area.Therefore, the respective tectonic stress field of each of the different stages in the complexdeformation of an area can be reconstructed in three steps: (1) geological structures formed atdifferent times are distinguished in remote sensing image interpretation; (2) structuraldeformation fields at different stages are determined by analyzing relationships betweenmicrostructures (joints and fractures) and the related structures (folds and faults); and (3)tectonic stress fields at different stages are respectively recovered through a study of the featuresof structural deformation fields in different periods. Circular structures and related circlular and radial joints are correlated in space to con-cealed structural rises. The authors propose a new method for establishing a natural model ofthe concealed structural rises and calculating the tectonic stress field by using quantitative dataof the remote sensing information of circular structures and related linear structures.展开更多
In order to research the field sensing characteristic of the carbon fiber smart material, the Tikhonov regularization principle and the modified Newton-Raphson(MNR) algorithm were adopted to solve the inverse problem ...In order to research the field sensing characteristic of the carbon fiber smart material, the Tikhonov regularization principle and the modified Newton-Raphson(MNR) algorithm were adopted to solve the inverse problem of the electrical resistance tomography(ERT). An ERT system of carbon fiber smart material was developed. Field sensing characteristic was researched with the experiment. The experimental results show that the specific resistance distribution of carbon fiber smart material is highly consistent with the distribution of structural strain. High resistance zone responds to high strain area, and the specific resistance distribution of carbon fiber smart material reflects the distribution of sample strain in covering area. Monitoring by carbon fiber smart material on complicated strain status in sample field domain is realized through theoretical and experimental study.展开更多
The spontaneous burning has been lasting for thousands of years in the coal fields in the north of China. It spreads from the west (Tianshan coal field) to the east (Huolinhe coal field). Its E-W extension is up to 37...The spontaneous burning has been lasting for thousands of years in the coal fields in the north of China. It spreads from the west (Tianshan coal field) to the east (Huolinhe coal field). Its E-W extension is up to 3750km, concentrating in N35°toN45°, its vertical depth up to 260m, and the surface temprature locally up to 270℃. Annually, it burns out 0, 250-300 million tones of coal, causing economic loss equivalent to 2-3 billion R.M.B. Yuan.It destroies coal resources and causes hazards in coal mines. In order to locate the extent and the direction in coal burning areas, the remote sensing technique has heen used and has produced an obvious benefit.展开更多
A high-sensitivity magnetic sensing system based on giant magneto-impedance(GMI)effect is designed and fabricated.The system comprises a GMI sensor equipped with a gradient probe and an signal acquisition and processi...A high-sensitivity magnetic sensing system based on giant magneto-impedance(GMI)effect is designed and fabricated.The system comprises a GMI sensor equipped with a gradient probe and an signal acquisition and processing module.A segmented superposition algorithm is used to increase target signal and reduce the random noise.The results show that under unshielded,room temperature conditions,the system achieves successful detection of weak magnetic fields down to 2 pT with a notable sensitivity of 1.84×10^(8)V/T(G=1000).By applying 17 overlays,the segmented superposition algorithm increases the power proportion of the target signal at 31 Hz from6.89%to 45.91%,surpassing the power proportion of the 2 Hz low-frequency interference signal.Simultaneously,it reduces the power proportion of the 20 Hz random noise.The segmented superposition process effectively cancels out certain random noise elements,leading to a reduction in their respective power proportions.This high-sensitivity magnetic sensing system features a simple structure,and is easy to operate,making it highly valuable for both practical applications and broader dissemination.展开更多
Developing microwave electric field sensing based on Rydberg atoms has received significant attention due to its unique advantages. However, achieving effective coupling between Rydberg atoms and the microwave electri...Developing microwave electric field sensing based on Rydberg atoms has received significant attention due to its unique advantages. However, achieving effective coupling between Rydberg atoms and the microwave electric field in the sensing process is a challenging problem that greatly impacts the sensitivity. To address this, we propose using a microwave resonant cavity to enhance the effective coupling between the Rydberg atoms and the microwave electric field. In our experiment, Rydberg atoms are prepared via a three-photon excitation scheme, and the electric fields are measured without and with a microwave cavity in which the vapor cell is placed inside, respectively. As a result, we achieved an 18 dB enhancement of power sensitivity by adding the cavity,which is an effective enhancement in electric field pulse signal detection. This experimental testing provides a promising direction for enhancing the sensitivity of Rydberg atomic electric field sensors and paves the way for their application in precision electric field measurements.展开更多
Optical fiber magnetic field sensors play a crucial role in aerospace and medical fields due to their high sensitivity,fast response time,and resistance to electromagnetic interference.Most current research primarily ...Optical fiber magnetic field sensors play a crucial role in aerospace and medical fields due to their high sensitivity,fast response time,and resistance to electromagnetic interference.Most current research primarily focuses on detecting magnetic field intensity;however,the magnetic field is a vector field with both intensity and direction,making vector magnetic field measurement significantly important in various fields.展开更多
The nitrogen-vacancy(NV)center in diamond is a point defect formed by a substitutional nitrogen atom adjacent to a carbon vacancy.Owing to its exceptional fluorescence properties and long quantum coherence,the NV cent...The nitrogen-vacancy(NV)center in diamond is a point defect formed by a substitutional nitrogen atom adjacent to a carbon vacancy.Owing to its exceptional fluorescence properties and long quantum coherence,the NV center has broad applications in quantum computing,quantum sensing,and magnetic field imaging.This study focuses on the magnetic field sensing capabilities of NV centers,with performance critically dependent on the NV concentrations and coherence time.High-performance NV center diamond samples were synthesized using microwave plasma chemical vapor deposition(MPCVD)with controlled nitrogen doping,followed by electron irradiation and high-temperature annealing.We obtained diamond samples with high NV concentrations and a coherence time of T_(2)*=0.48µs.These diamonds were processed into micrometer-sized crystals via laser cutting and polishing,then integrated into an optical fiber-based probe for magnetic field detection.The sensor’s performance was first characterized independently,with a magnetic sensitivity of 5.77nT/√Hz and a magnetic resolution of 0.1 G@4715 G.Subsequently,two-dimensional magnetic field imaging experiments were performed on chip surfaces,demonstrating the probe’s capability for precise mapping of local magnetic fields.展开更多
Field environmental sensing can acquire real-time environmental information,which will be applied to field operation,through the fusion of multiple sensors.Multi-sensor fusion refers to the fusion of information obtai...Field environmental sensing can acquire real-time environmental information,which will be applied to field operation,through the fusion of multiple sensors.Multi-sensor fusion refers to the fusion of information obtained from multiple sensors using more advanced data processing methods.The main objective of applying this technology in field environment perception is to acquire real-time environmental information,making agricultural mechanical devices operate better in complex farmland environment with stronger sensing ability and operational accuracy.In this paper,the characteristics of sensors are studied to clarify the advantages and existing problems of each type of sensors and point out that multiple sensors can be introduced to compensate for the information loss.Secondly,the mainstream information fusion types at present are outlined.The characteristics,advantages and disadvantages of different fusion methods are analyzed.The important studies and applications related to multi-sensor information fusion technology published at home and abroad are listed.Eventually,the existing problems in the field environment sensing at present are summarized and the prospect for future of sensors precise sensing,multi-dimensional fusion strategies,discrepancies in sensor fusion and agricultural information processing are proposed in hope of providing reference for the deeper development of smart agriculture.展开更多
A novel magnetic field sensing system based on the fiber loop ring-down technique is proposed in this paper. In the fiber loop, a U-bent single-mode-fiber structure coated with magnetic fluid(MF) serves as the sensing...A novel magnetic field sensing system based on the fiber loop ring-down technique is proposed in this paper. In the fiber loop, a U-bent single-mode-fiber structure coated with magnetic fluid(MF) serves as the sensing head, and an erbium-doped fiber amplifier(EDFA) is introduced to compensate for the intrinsic loss of the cavity. The ring-down time of the system varies with the change of applied magnetic field due to the tunable absorption coefficient and refractive index of the MF. Therefore, measurement of the magnetic field can be realized by monitoring the ringdown time. The experimental results show that the performance of the system is extremely dependent on the interrogation wavelength, because both the gain of the EDFA and the loss of the sensing head are wavelength dependent.We found that at the optimal wavelength, the ratio of the gain to loss attained its maximum. The sensing system was experimentally demonstrated and a sensitivity of-0.5951 μs∕Oe was achieved.展开更多
A kind of photonic crystal (PC) micro-cavity sensor based on magnetic fluid (MF) filling is designed with simulation model. Generally, many sensors’ designs are based on a universal temperature in the whole structure...A kind of photonic crystal (PC) micro-cavity sensor based on magnetic fluid (MF) filling is designed with simulation model. Generally, many sensors’ designs are based on a universal temperature in the whole structure. However, strong photothermal effect in high Q micro-cavities will lead to different temperatures between cavities and environment inevitably. In many theoretical PC sensor designs, researchers neglected the different temperature between environment and cavities. This simple hypothesis will probably lead to failure of sensor design and get wrong temperature. Moreover, few theoretical or experimental works have been done to study optical cavity’s heating process and temperature. We propose that researchers should take seriously about this point. Here, the designed cascaded micro-cavity structure has three spectral lines and a reversible sensitivity matrix, which can simultaneously detect magnetic field, ambient temperature and MF micro-cavity temperature. It can solve the magnetic field and temperature cross-sensitivity problem, and further, distinguish the different temperatures of environment and magnetic fluid cavities. The influence of hole radius and slab thickness on the depth and Q value of the resonant spectral line are also studied. Responses of three dips to magnetic field, ambient temperature and MF micro-cavity temperature are simulated, respectively, where dip 1 belongs to MF cavity 1, dip 2 and dip 3 belong to MF cavity 2. The obtained magnetic field sensitivities are 2.89 pm/Oe, 4.57 pm/Oe, and 5.14 pm/Oe, respectively;the ambient temperature sensitivities are 65.51 pm/K, 50.94 pm/K, and 58.98 pm/K, respectively;and the MF micro-cavity temperature sensitivities are −14.41 pm/K, −17.06 pm/K, and −18.81 pm/K, respectively.展开更多
The wearable sensors have recently attracted considerable attentions as communication interfaces through the information perception,decoding,and conveying process.However,it is still challenging to obtain a sensor tha...The wearable sensors have recently attracted considerable attentions as communication interfaces through the information perception,decoding,and conveying process.However,it is still challenging to obtain a sensor that can convert detectable signals into multiple outputs for convenient,e cient,cryptic,and high-capacity information transmission.Herein,we present a capacitive sensor of magnetic field based on a tilted flexible micromagnet array(t-FMA)as the proposed interaction interface.With the bidirectional bending capability of t-FMA actuated by magnetic torque,the sensor can recognize both the magnitude and orientation of magnetic field in real time with non-overlapping capacitance signals.The optimized sensor exhibits the high sensitivity of over 1.3 T-1 and detection limit down to 1 mT with excellent durability.As a proof of concept,the sensor has been successfully demonstrated for convenient,e cient,and programmable interaction systems,e.g.,touchless Morse code and Braille communication.The distinguishable recognition of the magnetic field orientation and magnitude further enables the sensor unit as a high-capacity transmitter for cryptic information interaction(e.g.,encoded ID recognition)and multi-control instruction outputting.We believe that the proposed magnetic field sensor can open up a potential avenue for future applications including information communication,virtual reality device,and interactive robotics.展开更多
Spin orbit torque(SOT)of spin current has provided an efficient manipulation of ferromagnet order,antiferromagnet order,and exchange bias field for various spintronic applications.Here,in contrast to the external magn...Spin orbit torque(SOT)of spin current has provided an efficient manipulation of ferromagnet order,antiferromagnet order,and exchange bias field for various spintronic applications.Here,in contrast to the external magnetic field which is very hard to apply locally,we propose to utilize the local control characteristic of SOT on the macro-nano-meter scale to set four different directions of exchange bias field at the IrMn/CoFe interface on one chip simultaneously.Moreover,with this fully electrical control technology to replace the existing various complex processes based on magnetic field annealing,we fabricate monolithic dual-axis full Wheatstone-bridge magnetoresistance sensors to detect two-dimensional magnetic field vector,which exhibit very high detection sensitivity of 9.45 nT-Hz^(1/2)and 12.3 nT-Hz^(1/2)at 10 Hz for X-axis and Y-axis sensing,respectively.This work provides a paradigm to simultaneously implement function configurations of spintronic devices by using the local control characteristic of SOT.展开更多
Metamaterials have earned their name with extraordinary properties such as negative refractive index and invisibility cloaking. With over 15 years of research and development, metamaterials show their debut in real wo...Metamaterials have earned their name with extraordinary properties such as negative refractive index and invisibility cloaking. With over 15 years of research and development, metamaterials show their debut in real world applications, especially in the areas of telecommunication, sensing, aerospace & defense, optics and medical instrumentation. In the meanwhile, metamaterials are expanding their concept in areas beyond electromagnetics. In this paper, the authors would like to focus on the research and applications in telecommunication and sensing. Octave-bandwidth horn antennas, flat-panel satellite antennas and air-borne holographic satellite antennas are all fabulous examples of clever implementation that bring metamaterials into practical devices. We would like to discuss the features that differentiate metamaterials from conventional counterparts in case studies. With the advancement in design, manufacturing, packaging, detection and testing, more sophisticated features are expected in the telecommunication, sensing, and beyond.展开更多
Miniaturized fiber-optic magnetic field sensors have attracted considerable interest owing to their superiorities in anti-electromagnetic interference and compactness.However,the intrinsic thermodynamic properties of ...Miniaturized fiber-optic magnetic field sensors have attracted considerable interest owing to their superiorities in anti-electromagnetic interference and compactness.However,the intrinsic thermodynamic properties of the material make temperature cross-sensitivity a challenging problem in terms of sensing accuracy and reliability.In this study,an ultracompact multicore fiber(MCF)tip sensor was designed to discriminatively measure the magnetic field and temperature,which was subsequently evaluated experimentally.The novel 3D printed sensing component consists of a bowl-shaped microcantilever and a polymer microfluid-infiltrated microcavity on the end-facet of an MCF,acting as two miniaturized Fabry-Perot interferometers.The magnetic sensitivity of the microcantilever was implemented by incorporating an iron micro ball into the microcantilever,and the microfluid-infiltrated microcavity enhanced the capability of highly sensitive temperature sensing.Using this tiny fiber-facet device in the two channels of an MCF allows discriminative measurements of the magnetic field and temperature by determining the sensitivity coefficient matrix of two parameters.The device exhibited a high magnetic field intensity sensitivity,approximately 1805.6 pm/mT with a fast response time of~213 ms and a high temperature sensitivity of 160.3 pm/℃.Moreover,the sensor had a low condition number of 11.28,indicating high reliability in two-parameter measurements.The proposed 3D printed MCF-tip probes,which detect multiple signals through multiple channels within a single fiber,can provide an ultracompact,sensitive,and reliable scheme for discriminative measurements.The bowl-shaped microcantilever also provides a useful platform for incorporating microstructures with functional materials,extending multi-parameter sensing scenarios and promoting the application of MCFs.展开更多
Luminescent Single-Molecule Magnets(SMMs)have gained broad scientific attention due to their potential applications in the dual sensing of temperature and magnetic field or optical thermometry for the self-monitoring ...Luminescent Single-Molecule Magnets(SMMs)have gained broad scientific attention due to their potential applications in the dual sensing of temperature and magnetic field or optical thermometry for the self-monitoring of temperature in SMM-based devices.We present a route toward thermoresponsive emissive SMMs based on linking two molecular components separately providing luminescent thermometry and SMM features.展开更多
Whispering gallery mode(WGM)microresonators emerged as a promising platform for highly sensitive sensing applications due to their high-quality factors and small mode volumes.They offer the advantages of the ultrahigh...Whispering gallery mode(WGM)microresonators emerged as a promising platform for highly sensitive sensing applications due to their high-quality factors and small mode volumes.They offer the advantages of the ultrahigh sensitivity and compact size,rendering them suitable across multiple fields.A stable encapsulation process is essential for practical applications to establish a reliable coupling system between the microcavity and its waveguide coupler,especially for the microtoroidal resonator and tapered fiber coupler.However,adjusting the coupling coefficient after the packaging process poses challenges,thereby compromising coupling accuracy and limiting its range of applications.It is imperative to provide a platform of tunable coupling for packaged WGM resonators.Here,we provide an approach for leveraging the magnetostrictive effect to dynamically regulate the fiber-cavity coupling,enabling the measurement of the magnetic field as an example.Moreover,we show the fine-tuning of coupling within the packaged WGM microresonator,allowing the precision control of the optomechanical effect.Through this method,a tunable coupling platform in a packaged system is realized,opening up new dimensions of research in various fields.展开更多
Rydberg atoms-based electric field sensing has developed rapidly over the past decade.A variety of theoretical proposals and experiment configurations are suggested and realized to improve the measurement metrics,such...Rydberg atoms-based electric field sensing has developed rapidly over the past decade.A variety of theoretical proposals and experiment configurations are suggested and realized to improve the measurement metrics,such as intensity sensitivity,bandwidth,phase,and accuracy.The Stark effect and electromagnetically induced transparency(EIT)or electromagnetically induced absorption(EIA)are fundamental physics principles behind the stage.Furthermore,various techniques such as amplitude-or frequency-modulation,optical homodyne read-out,microwave superheterodyne and frequency conversion based on multi-wave mixing in atoms are utilized to push the metrics into higher levels.In this review,different technologies and the corresponding metrics they had achieved were presented,hoping to inspire more possibilities in the improvement of metrics of Rydberg atom-based electric field sensing and broadness of application scenarios.展开更多
The ability of perceiving external pressures and conducting corresponding signals is one of the important functions of flexible electronics,which has been widely studied in electronic skin,prosthetics,robotics,healthc...The ability of perceiving external pressures and conducting corresponding signals is one of the important functions of flexible electronics,which has been widely studied in electronic skin,prosthetics,robotics,healthcare,human-machine interfaces,etc.Pressure sensor should not be limited to the detection of unidirectional pressure.Here,a leather-based electronic pressure sensor and corresponding arrays with bidirectional sensing capability are demonstrated.The sensor/arrays consisting of two pieces of stacked leather both modified with acidified carbon nanotubes(a-CNTs)can achieve multi-level response to pressure over a broad working range and sense pulling force opposite to pressure.With polyurethane mixed with ferriferrous oxide(Fe3O4)powder being applied to their upper surface,the resistive sensor/individual units of arrays can also detect the magnetic field because of the contactless pulling force generated by the magnetized Fe3O4.Being able to sense pressure,pulling force and magnetic field,the leather-based electronic bidirectional pressure sensor and corresponding arrays with good performance not only exhibit potential for mass production and their broad application prospects,but also provide a new insight for the development of flexible electronics.展开更多
基金This study was sponsored by The Open Research Laboratory of Quantitative Prediction,Exploration and Assessment of Mineral Resources,MGMR,China.
文摘The structural feature shown on a remote sensing image is a synthetic result ofcombination of the deformations produced during the entire geological history of an area.Therefore, the respective tectonic stress field of each of the different stages in the complexdeformation of an area can be reconstructed in three steps: (1) geological structures formed atdifferent times are distinguished in remote sensing image interpretation; (2) structuraldeformation fields at different stages are determined by analyzing relationships betweenmicrostructures (joints and fractures) and the related structures (folds and faults); and (3)tectonic stress fields at different stages are respectively recovered through a study of the featuresof structural deformation fields in different periods. Circular structures and related circlular and radial joints are correlated in space to con-cealed structural rises. The authors propose a new method for establishing a natural model ofthe concealed structural rises and calculating the tectonic stress field by using quantitative dataof the remote sensing information of circular structures and related linear structures.
基金Funded by the National High-tech Research and Development Program of China(863 Program)(No.2013AA031306)
文摘In order to research the field sensing characteristic of the carbon fiber smart material, the Tikhonov regularization principle and the modified Newton-Raphson(MNR) algorithm were adopted to solve the inverse problem of the electrical resistance tomography(ERT). An ERT system of carbon fiber smart material was developed. Field sensing characteristic was researched with the experiment. The experimental results show that the specific resistance distribution of carbon fiber smart material is highly consistent with the distribution of structural strain. High resistance zone responds to high strain area, and the specific resistance distribution of carbon fiber smart material reflects the distribution of sample strain in covering area. Monitoring by carbon fiber smart material on complicated strain status in sample field domain is realized through theoretical and experimental study.
文摘The spontaneous burning has been lasting for thousands of years in the coal fields in the north of China. It spreads from the west (Tianshan coal field) to the east (Huolinhe coal field). Its E-W extension is up to 3750km, concentrating in N35°toN45°, its vertical depth up to 260m, and the surface temprature locally up to 270℃. Annually, it burns out 0, 250-300 million tones of coal, causing economic loss equivalent to 2-3 billion R.M.B. Yuan.It destroies coal resources and causes hazards in coal mines. In order to locate the extent and the direction in coal burning areas, the remote sensing technique has heen used and has produced an obvious benefit.
基金National Natural Science Foundation of China(No.51977214)。
文摘A high-sensitivity magnetic sensing system based on giant magneto-impedance(GMI)effect is designed and fabricated.The system comprises a GMI sensor equipped with a gradient probe and an signal acquisition and processing module.A segmented superposition algorithm is used to increase target signal and reduce the random noise.The results show that under unshielded,room temperature conditions,the system achieves successful detection of weak magnetic fields down to 2 pT with a notable sensitivity of 1.84×10^(8)V/T(G=1000).By applying 17 overlays,the segmented superposition algorithm increases the power proportion of the target signal at 31 Hz from6.89%to 45.91%,surpassing the power proportion of the 2 Hz low-frequency interference signal.Simultaneously,it reduces the power proportion of the 20 Hz random noise.The segmented superposition process effectively cancels out certain random noise elements,leading to a reduction in their respective power proportions.This high-sensitivity magnetic sensing system features a simple structure,and is easy to operate,making it highly valuable for both practical applications and broader dissemination.
基金the fundings from National Key R&D Program of China (Grant No. 2022YFA1404002)National Natural Science Foundation of China (Grant Nos. T2495253, U20A20218, 61525504, and 61435011)+4 种基金Anhui Initiative in Quantum Information Technologies (Grant No. AHY020200)Major Science and Technology Projects in Anhui Province (Grant No. 202203a13010001)Youth Innovation Promotion Association of the Chinese Academy of Sciences (Grant No. 2018490)the fundings from Anhui Provincial Department of Education (Grant No. YQZD2024061)Research Program of Higher Education Institutions in Anhui Province (Grant No. 2024AH050645)。
文摘Developing microwave electric field sensing based on Rydberg atoms has received significant attention due to its unique advantages. However, achieving effective coupling between Rydberg atoms and the microwave electric field in the sensing process is a challenging problem that greatly impacts the sensitivity. To address this, we propose using a microwave resonant cavity to enhance the effective coupling between the Rydberg atoms and the microwave electric field. In our experiment, Rydberg atoms are prepared via a three-photon excitation scheme, and the electric fields are measured without and with a microwave cavity in which the vapor cell is placed inside, respectively. As a result, we achieved an 18 dB enhancement of power sensitivity by adding the cavity,which is an effective enhancement in electric field pulse signal detection. This experimental testing provides a promising direction for enhancing the sensitivity of Rydberg atomic electric field sensors and paves the way for their application in precision electric field measurements.
基金National Natural Science Foundation of China(62075124,62275148).
文摘Optical fiber magnetic field sensors play a crucial role in aerospace and medical fields due to their high sensitivity,fast response time,and resistance to electromagnetic interference.Most current research primarily focuses on detecting magnetic field intensity;however,the magnetic field is a vector field with both intensity and direction,making vector magnetic field measurement significantly important in various fields.
基金financial support by the National Key Research and Development Program of China (Grant No. 2021YFB2012600)the Fund of National Key laboratory of Plasma Physics (Grant No. 6142A04240204)+5 种基金the National Natural Science Foundation of China (Grant No. 62474165)the Science and Technology Major Project of Henan Province (Grant No. 231100230300)the Henan Association for Science and Technology Youth Talent Support Program (Grant No. 2024HYTP024)the Key Research and Development Project of Henan Province (Grant No. 231111232100)the Natural Science Foundation of Henan Province (Grant No. 252300421228)Zhongyuan Science and Technology Innovation Youth Top Talent Program
文摘The nitrogen-vacancy(NV)center in diamond is a point defect formed by a substitutional nitrogen atom adjacent to a carbon vacancy.Owing to its exceptional fluorescence properties and long quantum coherence,the NV center has broad applications in quantum computing,quantum sensing,and magnetic field imaging.This study focuses on the magnetic field sensing capabilities of NV centers,with performance critically dependent on the NV concentrations and coherence time.High-performance NV center diamond samples were synthesized using microwave plasma chemical vapor deposition(MPCVD)with controlled nitrogen doping,followed by electron irradiation and high-temperature annealing.We obtained diamond samples with high NV concentrations and a coherence time of T_(2)*=0.48µs.These diamonds were processed into micrometer-sized crystals via laser cutting and polishing,then integrated into an optical fiber-based probe for magnetic field detection.The sensor’s performance was first characterized independently,with a magnetic sensitivity of 5.77nT/√Hz and a magnetic resolution of 0.1 G@4715 G.Subsequently,two-dimensional magnetic field imaging experiments were performed on chip surfaces,demonstrating the probe’s capability for precise mapping of local magnetic fields.
基金supported by the National Natural Science Foundation of China(Grant No.52272438)the Jiangsu Agricultural Science and Technology Innovation[Grant No.CX(21)3149]+1 种基金the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(Grant No.Yueshengjihua-2206)the Jiangsu Province and Education Ministry Co-sponsored Synergistic Innovation Center of Modern Agricultural Equipment(Grant No.XTCX2007).
文摘Field environmental sensing can acquire real-time environmental information,which will be applied to field operation,through the fusion of multiple sensors.Multi-sensor fusion refers to the fusion of information obtained from multiple sensors using more advanced data processing methods.The main objective of applying this technology in field environment perception is to acquire real-time environmental information,making agricultural mechanical devices operate better in complex farmland environment with stronger sensing ability and operational accuracy.In this paper,the characteristics of sensors are studied to clarify the advantages and existing problems of each type of sensors and point out that multiple sensors can be introduced to compensate for the information loss.Secondly,the mainstream information fusion types at present are outlined.The characteristics,advantages and disadvantages of different fusion methods are analyzed.The important studies and applications related to multi-sensor information fusion technology published at home and abroad are listed.Eventually,the existing problems in the field environment sensing at present are summarized and the prospect for future of sensors precise sensing,multi-dimensional fusion strategies,discrepancies in sensor fusion and agricultural information processing are proposed in hope of providing reference for the deeper development of smart agriculture.
基金National Key Scientific Instrument and Equipment Development Project of China(2013YQ03091502)National Natural Science Foundation of China(NSFC)(61378043,61107035)
文摘A novel magnetic field sensing system based on the fiber loop ring-down technique is proposed in this paper. In the fiber loop, a U-bent single-mode-fiber structure coated with magnetic fluid(MF) serves as the sensing head, and an erbium-doped fiber amplifier(EDFA) is introduced to compensate for the intrinsic loss of the cavity. The ring-down time of the system varies with the change of applied magnetic field due to the tunable absorption coefficient and refractive index of the MF. Therefore, measurement of the magnetic field can be realized by monitoring the ringdown time. The experimental results show that the performance of the system is extremely dependent on the interrogation wavelength, because both the gain of the EDFA and the loss of the sensing head are wavelength dependent.We found that at the optimal wavelength, the ratio of the gain to loss attained its maximum. The sensing system was experimentally demonstrated and a sensitivity of-0.5951 μs∕Oe was achieved.
文摘A kind of photonic crystal (PC) micro-cavity sensor based on magnetic fluid (MF) filling is designed with simulation model. Generally, many sensors’ designs are based on a universal temperature in the whole structure. However, strong photothermal effect in high Q micro-cavities will lead to different temperatures between cavities and environment inevitably. In many theoretical PC sensor designs, researchers neglected the different temperature between environment and cavities. This simple hypothesis will probably lead to failure of sensor design and get wrong temperature. Moreover, few theoretical or experimental works have been done to study optical cavity’s heating process and temperature. We propose that researchers should take seriously about this point. Here, the designed cascaded micro-cavity structure has three spectral lines and a reversible sensitivity matrix, which can simultaneously detect magnetic field, ambient temperature and MF micro-cavity temperature. It can solve the magnetic field and temperature cross-sensitivity problem, and further, distinguish the different temperatures of environment and magnetic fluid cavities. The influence of hole radius and slab thickness on the depth and Q value of the resonant spectral line are also studied. Responses of three dips to magnetic field, ambient temperature and MF micro-cavity temperature are simulated, respectively, where dip 1 belongs to MF cavity 1, dip 2 and dip 3 belong to MF cavity 2. The obtained magnetic field sensitivities are 2.89 pm/Oe, 4.57 pm/Oe, and 5.14 pm/Oe, respectively;the ambient temperature sensitivities are 65.51 pm/K, 50.94 pm/K, and 58.98 pm/K, respectively;and the MF micro-cavity temperature sensitivities are −14.41 pm/K, −17.06 pm/K, and −18.81 pm/K, respectively.
基金supported by The Science and Technology Development Fund,Macao SAR(File No.0037/2018/A1,0026/2020/AGJ)MultiYear Research Grant funded by University of Macao(File No.MYRG2017-00089-FST,MYRG2018-00063-IAPME)。
文摘The wearable sensors have recently attracted considerable attentions as communication interfaces through the information perception,decoding,and conveying process.However,it is still challenging to obtain a sensor that can convert detectable signals into multiple outputs for convenient,e cient,cryptic,and high-capacity information transmission.Herein,we present a capacitive sensor of magnetic field based on a tilted flexible micromagnet array(t-FMA)as the proposed interaction interface.With the bidirectional bending capability of t-FMA actuated by magnetic torque,the sensor can recognize both the magnitude and orientation of magnetic field in real time with non-overlapping capacitance signals.The optimized sensor exhibits the high sensitivity of over 1.3 T-1 and detection limit down to 1 mT with excellent durability.As a proof of concept,the sensor has been successfully demonstrated for convenient,e cient,and programmable interaction systems,e.g.,touchless Morse code and Braille communication.The distinguishable recognition of the magnetic field orientation and magnitude further enables the sensor unit as a high-capacity transmitter for cryptic information interaction(e.g.,encoded ID recognition)and multi-control instruction outputting.We believe that the proposed magnetic field sensor can open up a potential avenue for future applications including information communication,virtual reality device,and interactive robotics.
基金supported by the National Natural Science Foundation of China(51901008)the Major Basic Research Project of Shandong Province(ZR2020ZD28).
文摘Spin orbit torque(SOT)of spin current has provided an efficient manipulation of ferromagnet order,antiferromagnet order,and exchange bias field for various spintronic applications.Here,in contrast to the external magnetic field which is very hard to apply locally,we propose to utilize the local control characteristic of SOT on the macro-nano-meter scale to set four different directions of exchange bias field at the IrMn/CoFe interface on one chip simultaneously.Moreover,with this fully electrical control technology to replace the existing various complex processes based on magnetic field annealing,we fabricate monolithic dual-axis full Wheatstone-bridge magnetoresistance sensors to detect two-dimensional magnetic field vector,which exhibit very high detection sensitivity of 9.45 nT-Hz^(1/2)and 12.3 nT-Hz^(1/2)at 10 Hz for X-axis and Y-axis sensing,respectively.This work provides a paradigm to simultaneously implement function configurations of spintronic devices by using the local control characteristic of SOT.
基金supported by Guangdong Innovative Research Team Program(Grant No.2009010005)State Key Laboratory of Meta-RF Electromagnetic Modulation Technology,Shenzhen Innovation P&D Team Program(Peacock Plan)(Grant No.KQE201106020031A)Guangdong Natural Science Funds for Distinguished Young Scholar(Grant No.S20120011253)“Metamaterial Design Method and System”
文摘Metamaterials have earned their name with extraordinary properties such as negative refractive index and invisibility cloaking. With over 15 years of research and development, metamaterials show their debut in real world applications, especially in the areas of telecommunication, sensing, aerospace & defense, optics and medical instrumentation. In the meanwhile, metamaterials are expanding their concept in areas beyond electromagnetics. In this paper, the authors would like to focus on the research and applications in telecommunication and sensing. Octave-bandwidth horn antennas, flat-panel satellite antennas and air-borne holographic satellite antennas are all fabulous examples of clever implementation that bring metamaterials into practical devices. We would like to discuss the features that differentiate metamaterials from conventional counterparts in case studies. With the advancement in design, manufacturing, packaging, detection and testing, more sophisticated features are expected in the telecommunication, sensing, and beyond.
基金supported by the National Natural Science Foundation of China(No.62275052,No.62275148)Shanghai 2021 Science and Technology International Cooperation Project“Program of Action for Science and Technology Innovation”(21530710400)+1 种基金the Jiangsu Province's Industry Outlook and Key Core Technologies-Key Projects(BE2022055-4)the Open Fund of Laboratory of Science and Technology on Marine Navigation and Control,China State Shipbuilding Corporation(2023010102).
文摘Miniaturized fiber-optic magnetic field sensors have attracted considerable interest owing to their superiorities in anti-electromagnetic interference and compactness.However,the intrinsic thermodynamic properties of the material make temperature cross-sensitivity a challenging problem in terms of sensing accuracy and reliability.In this study,an ultracompact multicore fiber(MCF)tip sensor was designed to discriminatively measure the magnetic field and temperature,which was subsequently evaluated experimentally.The novel 3D printed sensing component consists of a bowl-shaped microcantilever and a polymer microfluid-infiltrated microcavity on the end-facet of an MCF,acting as two miniaturized Fabry-Perot interferometers.The magnetic sensitivity of the microcantilever was implemented by incorporating an iron micro ball into the microcantilever,and the microfluid-infiltrated microcavity enhanced the capability of highly sensitive temperature sensing.Using this tiny fiber-facet device in the two channels of an MCF allows discriminative measurements of the magnetic field and temperature by determining the sensitivity coefficient matrix of two parameters.The device exhibited a high magnetic field intensity sensitivity,approximately 1805.6 pm/mT with a fast response time of~213 ms and a high temperature sensitivity of 160.3 pm/℃.Moreover,the sensor had a low condition number of 11.28,indicating high reliability in two-parameter measurements.The proposed 3D printed MCF-tip probes,which detect multiple signals through multiple channels within a single fiber,can provide an ultracompact,sensitive,and reliable scheme for discriminative measurements.The bowl-shaped microcantilever also provides a useful platform for incorporating microstructures with functional materials,extending multi-parameter sensing scenarios and promoting the application of MCFs.
基金financed by the National Science Centre of Poland,the OPUS-21 project,no.2021/41/B/ST5/02544The research has been supported by an infrastructure grant from the Faculty of Chemistry under the Strategic Programme Excellence Initiative at Jagiellonian Univ.The study was carried out using the research infrastructure co-funded by the EU in the framework of the Smart Growth Operational Program,Measure 4.2+1 种基金Grant No.POIR.04.02.00-00-D001/20,“ATOMIN 2.0-ATOMic scale science for the INnovative economy”We also gratefully acknowledge Polish high-performance computing infrastructure PLGrid(HPC Center:ACK Cyfronet AGH)for providing computer facilities and support within computational grant no.PLG/2019/013095.
文摘Luminescent Single-Molecule Magnets(SMMs)have gained broad scientific attention due to their potential applications in the dual sensing of temperature and magnetic field or optical thermometry for the self-monitoring of temperature in SMM-based devices.We present a route toward thermoresponsive emissive SMMs based on linking two molecular components separately providing luminescent thermometry and SMM features.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFB2805600)the National Natural Science Foundation of China(Grant No.62131002)+3 种基金the National Natural Science Foundation of China(Grant No.62433015)the Leading Scholar of Xi’an Jiaotong University,Chinathe Laoshan Laboratory,China(Grant No.LSKJ202200900)the Innovative Leading Talent Project of“Shuangqian Plan”in Jiangxi Province,China.
文摘Whispering gallery mode(WGM)microresonators emerged as a promising platform for highly sensitive sensing applications due to their high-quality factors and small mode volumes.They offer the advantages of the ultrahigh sensitivity and compact size,rendering them suitable across multiple fields.A stable encapsulation process is essential for practical applications to establish a reliable coupling system between the microcavity and its waveguide coupler,especially for the microtoroidal resonator and tapered fiber coupler.However,adjusting the coupling coefficient after the packaging process poses challenges,thereby compromising coupling accuracy and limiting its range of applications.It is imperative to provide a platform of tunable coupling for packaged WGM resonators.Here,we provide an approach for leveraging the magnetostrictive effect to dynamically regulate the fiber-cavity coupling,enabling the measurement of the magnetic field as an example.Moreover,we show the fine-tuning of coupling within the packaged WGM microresonator,allowing the precision control of the optomechanical effect.Through this method,a tunable coupling platform in a packaged system is realized,opening up new dimensions of research in various fields.
基金supported by the National Key R&D Program of China(2022YFA1404000,2021YFA1402004,and 2022YFA1405300)the National Natural Science Foundation of China(61827824,61975104,12225405,U20A2074,U20A20218,61525504,and 61435011)+3 种基金the Innovation Program for Quantum Science and Technology(2021ZD0301700)the Fund for Science and Technology on Electronic Information Control Laboratory and the Fund for Shanxi“331 Project”Key Subjects Construction,Bairen Project of Shanxi Province,China,the Anhui Initiative in Quantum Information Technologies(AHY020200)the Major Science and Technology Projects in Anhui Province(202203a13010001)National Research Foundation,Prime Ministers Office,Singapore and the Ministry of Education,Singapore under the Research Centres of Excellence programme.
文摘Rydberg atoms-based electric field sensing has developed rapidly over the past decade.A variety of theoretical proposals and experiment configurations are suggested and realized to improve the measurement metrics,such as intensity sensitivity,bandwidth,phase,and accuracy.The Stark effect and electromagnetically induced transparency(EIT)or electromagnetically induced absorption(EIA)are fundamental physics principles behind the stage.Furthermore,various techniques such as amplitude-or frequency-modulation,optical homodyne read-out,microwave superheterodyne and frequency conversion based on multi-wave mixing in atoms are utilized to push the metrics into higher levels.In this review,different technologies and the corresponding metrics they had achieved were presented,hoping to inspire more possibilities in the improvement of metrics of Rydberg atom-based electric field sensing and broadness of application scenarios.
基金the National Natural Science Foundation for Distinguished Young Scholars(Grant No.21625401)the National Natural Science Foundation of China(Grant Nos.21727808,21574065,21604038,21504043,21604040 and 51702155)+2 种基金the Jiangsu Provincial Founds for Natural Science Foundation(Grant Nos.BK20160975,BK20160981 and BK20170975)the Program for Outstanding Young Scholars from the Organization Department of the CPC Central Committee,the National Key Basic Research Program of China(Grant No.2015CB932200)the National Key R&D Program of China(Grant No.2017YFA0207201)。
文摘The ability of perceiving external pressures and conducting corresponding signals is one of the important functions of flexible electronics,which has been widely studied in electronic skin,prosthetics,robotics,healthcare,human-machine interfaces,etc.Pressure sensor should not be limited to the detection of unidirectional pressure.Here,a leather-based electronic pressure sensor and corresponding arrays with bidirectional sensing capability are demonstrated.The sensor/arrays consisting of two pieces of stacked leather both modified with acidified carbon nanotubes(a-CNTs)can achieve multi-level response to pressure over a broad working range and sense pulling force opposite to pressure.With polyurethane mixed with ferriferrous oxide(Fe3O4)powder being applied to their upper surface,the resistive sensor/individual units of arrays can also detect the magnetic field because of the contactless pulling force generated by the magnetized Fe3O4.Being able to sense pressure,pulling force and magnetic field,the leather-based electronic bidirectional pressure sensor and corresponding arrays with good performance not only exhibit potential for mass production and their broad application prospects,but also provide a new insight for the development of flexible electronics.
