In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fib...In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fiber was used to adjust the rotation of the polarization direction caused by the optical isolator.The whole optical path structure,including the laser chip,lens,fiber,and modulator chip,was simulated to achieve high optical output efficiency.After a series of process improvements,a module with an output extinction ratio of 34 dB and a bandwidth of 20.5 GHz(from 2 GHz)was obtained.The optical output efficiency of the whole module reached approximately 21%.The link performance of the module was also measured.展开更多
An accurate technique for measuring the frequency response of semiconductor laser diode chips is proposed and experimentally demonstrated.The effects of test jig parasites can be completely removed in the measurement ...An accurate technique for measuring the frequency response of semiconductor laser diode chips is proposed and experimentally demonstrated.The effects of test jig parasites can be completely removed in the measurement by a new calibration method.In theory,the measuring range of the measurement system is only determined by the measuring range of the instruments network analyzer and photo detector.Diodes' bandwidth of 7 5GHz and 10GHz is measured.The results reveal that the method is feasible and comparing with other method,it is more precise and easier to use.展开更多
The use of a CO2 laser system for fabrication of microfluidic chip on polymethyl methacrylate （PMMA） is presented to reduce fabrication cost and time of chip. The grooving process of the laser system and a model for...The use of a CO2 laser system for fabrication of microfluidic chip on polymethyl methacrylate （PMMA） is presented to reduce fabrication cost and time of chip. The grooving process of the laser system and a model for the depth of microchannels are investigated. The relations between the depth of laser-cut channels and the laser beam power, velocity or the number of passes of the beam along the same channel are evaluated. In the experiments, the laser beam power varies from 0 to 50 W, the laser beam scanning velocity varies from 0 to 1 000 mm/s and the passes vary in the range of 1 to 10 times. Based on the principle of conservation of energy, the influence of the laser beam velocity, the laser power and the number of groove passes are examine. Considering the grooving interval energy loss, a modified mathematical model has been obtained and experimental data show good agreement with the theoretical model. This approach provides a simple way of predicting groove depths. The system provides a cost alternative of the other methods and it is especially useful on research work of rnicrofluidic prototyping due to the short cycle time of production.展开更多
A combined detection system involving simultaneous LIF and contacfless-conductometric measurements at the same place of the microfluidic chip was described. The LIF measurement was designed according to the confocal p...A combined detection system involving simultaneous LIF and contacfless-conductometric measurements at the same place of the microfluidic chip was described. The LIF measurement was designed according to the confocal principle and a moveable contactless-conduetivity detector was used in C^4D. Both measurements were mutually independent and advantageous in analyses of mixtures. Various experimental parameters affecting the response were examined and optimized. The performances were demonstrated by simultaneous detection of Rhodamine B. And the results showed that the combined detection system could be used sensitively and reliably.展开更多
In this paper,a lifted Haar transform(LHT)image compression optical chip has been researched to achieve rapid image compression.The chip comprises 32 same image compression optical circuits,and each circuit contains a...In this paper,a lifted Haar transform(LHT)image compression optical chip has been researched to achieve rapid image compression.The chip comprises 32 same image compression optical circuits,and each circuit contains a 2×2 multimode interference(MMI)coupler and aπ/2 delay line phase shifter as the key components.The chip uses highly borosilicate glass as the substrate,Su8 negative photoresist as the core layer,and air as the cladding layer.Its horizontal and longitudinal dimensions are 8011μm×10000μm.Simulation results present that the designed optical circuit has a coupling ratio(CR)of 0:100 and an insertion loss(IL)of 0.001548 d B.Then the chip is fabricated by femtosecond laser and testing results illustrate that the chip has a CR of 6:94 and an IL of 0.518 d B.So,the prepared chip possesses good image compression performance.展开更多
Spiking neural networks(SNNs)utilize brain-like spatiotemporal spike encoding for simulating brain functions.Photonic SNN offers an ultrahigh speed and power efficiency platform for implementing high-performance neuro...Spiking neural networks(SNNs)utilize brain-like spatiotemporal spike encoding for simulating brain functions.Photonic SNN offers an ultrahigh speed and power efficiency platform for implementing high-performance neuromorphic computing.Here,we proposed a multi-synaptic photonic SNN,combining the modified remote supervised learning with delayweight co-training to achieve pattern classification.The impact of multi-synaptic connections and the robustness of the network were investigated through numerical simulations.In addition,the collaborative computing of algorithm and hardware was demonstrated based on a fabricated integrated distributed feedback laser with a saturable absorber(DFB-SA),where 10 different noisy digital patterns were successfully classified.A functional photonic SNN that far exceeds the scale limit of hardware integration was achieved based on time-division multiplexing,demonstrating the capability of hardware-algorithm co-computation.展开更多
Orbital angular momentum(OAM)modes have emerged as a promising solution for enhancing the capacity of optical multiplexing systems,leveraging their theoretically unbounded set of orthogonal spatial modes.However,the g...Orbital angular momentum(OAM)modes have emerged as a promising solution for enhancing the capacity of optical multiplexing systems,leveraging their theoretically unbounded set of orthogonal spatial modes.However,the generation and detection of OAM multiplexing signals are predominantly reliant on bulky optical components within complex optical setups.We introduce a compact solution for OAM information processing using laser-written glass chips,facilitating efficient multiplexing and demultiplexing of multiple OAM information channels.During the multiplexing process,OAM channels are managed via laser-scribed single-mode waveguides within a glass chip,with their modes converted using laser-written holograms on the side wall of the glass chip.The reciprocal process is employed for OAM demultiplexing.Our chips seamlessly interface with commercial optical fibers,ensuring compatibility with existing fiber-optic communication infrastructure.This work not only establishes,to our knowledge,a novel approach for OAM optical multiplexing but also underscores the potential of laser writing technology in advancing photonics and its practical applications in optical communications.展开更多
In this study, tetrahedral amorphous carbon (ta-C) films with thicknesses between several 100 nm and several micrometers have been deposited onto polished tungsten carbide and steel substrates by pulsed laser depositi...In this study, tetrahedral amorphous carbon (ta-C) films with thicknesses between several 100 nm and several micrometers have been deposited onto polished tungsten carbide and steel substrates by pulsed laser deposition (PLD) using an excimer laser (248 nm wavelength). We investigate the optical properties (e.g. the refractive index (n) and extinction coefficient (k) in the visible and near-infrared wavelength range) of these layers in dependence of the used laser ablation fluence on the target. It is shown that n of ~2000 nm thick ta-C films can be tuned, depending on the sp3-content, between n = 2.5 and 2.8 at a wavelength of 632 nm. Besides of this k reduces with the sp3-content and is as low as 0.03 at sp3-contents of more than 75%. We proof that this gives the opportunity to prepare coating with tailored optical properties. Furthermore, it is shown that the ta-C films have low background fluorescence in the wavelengths range of 380 - 750 nm, which make this thin films attractive for certain optical, medical and biotechnological applications. We present for the first time that one possible application is the use in Lab-on-a-Chip-systems (LOC). Within these systems, the ultrasensitive detection of fluorescence markers and dyes is a challenge. In order to increase the signal-to-noise-ratio, a setup was developed, that used the specific optical properties of ta-C films produced by PLD. We used the ta-C film as an integrated reflector that combined low background fluorescence, a low reflectivity at the excitation wavelength and the high reflectivity at the emission wavelength. We prove that this setup improves the detection of fluorescence photons.展开更多
Ytterbium ion(Yb^(3+))-doped lasers are widely used in precision machining and precision measurement fields because of their high efficiency and high power,which are primarily based on solid-state lasers and fiber las...Ytterbium ion(Yb^(3+))-doped lasers are widely used in precision machining and precision measurement fields because of their high efficiency and high power,which are primarily based on solid-state lasers and fiber lasers.Here,we demonstrate an on-chip Yb^(3+)-doped thin-film lithium niobate(Yb:TFLN)Fabry-Perot microcavity laser.We achieve single-frequency laser operation at 1030 and 1060 nm with a side-mode suppression ratio above 30 dB,an emission linewidth below 40 pm,and an output power up to 1.5 mW at 1060 nm and 0.3 mW at 1030 nm.In addition,using the electro-optic effect of lithium niobate,we achieve a laser tuning efficiency of 4 pm/V.This work opens the path to on-chip high-power and mode-locked ultrafast laser output.展开更多
基金This work was supported by National Key Research and Development Program of China(2018YFB2201101)the Strategic Priority Research Program of Chinese Academy of Sciences,Grant No.XDB43000000Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park No.Z201100004020004。
文摘In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fiber was used to adjust the rotation of the polarization direction caused by the optical isolator.The whole optical path structure,including the laser chip,lens,fiber,and modulator chip,was simulated to achieve high optical output efficiency.After a series of process improvements,a module with an output extinction ratio of 34 dB and a bandwidth of 20.5 GHz(from 2 GHz)was obtained.The optical output efficiency of the whole module reached approximately 21%.The link performance of the module was also measured.
文摘An accurate technique for measuring the frequency response of semiconductor laser diode chips is proposed and experimentally demonstrated.The effects of test jig parasites can be completely removed in the measurement by a new calibration method.In theory,the measuring range of the measurement system is only determined by the measuring range of the instruments network analyzer and photo detector.Diodes' bandwidth of 7 5GHz and 10GHz is measured.The results reveal that the method is feasible and comparing with other method,it is more precise and easier to use.
基金This project is supported by National Hi-tech Research and Development Program of China (863 Program, No.2002AA421150)Specialized Research Fund for the Doctoral Program of Higher Education of China (No.20030335091).
文摘The use of a CO2 laser system for fabrication of microfluidic chip on polymethyl methacrylate （PMMA） is presented to reduce fabrication cost and time of chip. The grooving process of the laser system and a model for the depth of microchannels are investigated. The relations between the depth of laser-cut channels and the laser beam power, velocity or the number of passes of the beam along the same channel are evaluated. In the experiments, the laser beam power varies from 0 to 50 W, the laser beam scanning velocity varies from 0 to 1 000 mm/s and the passes vary in the range of 1 to 10 times. Based on the principle of conservation of energy, the influence of the laser beam velocity, the laser power and the number of groove passes are examine. Considering the grooving interval energy loss, a modified mathematical model has been obtained and experimental data show good agreement with the theoretical model. This approach provides a simple way of predicting groove depths. The system provides a cost alternative of the other methods and it is especially useful on research work of rnicrofluidic prototyping due to the short cycle time of production.
文摘A combined detection system involving simultaneous LIF and contacfless-conductometric measurements at the same place of the microfluidic chip was described. The LIF measurement was designed according to the confocal principle and a moveable contactless-conduetivity detector was used in C^4D. Both measurements were mutually independent and advantageous in analyses of mixtures. Various experimental parameters affecting the response were examined and optimized. The performances were demonstrated by simultaneous detection of Rhodamine B. And the results showed that the combined detection system could be used sensitively and reliably.
基金the Natural Science Foundation of Hubei Province(No.2017CFB685)Hubei University of Technology"Advanced Manufacturing Technology and Equipment"Collaborative Innovation Center Open Research Fund(Nos.038/1201501 and 038/1201803)the College-level Project of Hubei University of Technology(Nos.4201/01758,4201/01802,4201/01889,and 4128/21025)。
文摘In this paper,a lifted Haar transform(LHT)image compression optical chip has been researched to achieve rapid image compression.The chip comprises 32 same image compression optical circuits,and each circuit contains a 2×2 multimode interference(MMI)coupler and aπ/2 delay line phase shifter as the key components.The chip uses highly borosilicate glass as the substrate,Su8 negative photoresist as the core layer,and air as the cladding layer.Its horizontal and longitudinal dimensions are 8011μm×10000μm.Simulation results present that the designed optical circuit has a coupling ratio(CR)of 0:100 and an insertion loss(IL)of 0.001548 d B.Then the chip is fabricated by femtosecond laser and testing results illustrate that the chip has a CR of 6:94 and an IL of 0.518 d B.So,the prepared chip possesses good image compression performance.
基金supports from the National Key Research and Development Program of China (Nos.2021YFB2801900,2021YFB2801901,2021YFB2801902,2021YFB2801903,2021YFB2801904)the National Outstanding Youth Science Fund Project of National Natural Science Foundation of China (No.62022062)+1 种基金the National Natural Science Foundation of China (No.61974177)the Fundamental Research Funds for the Central Universities (No.QTZX23041).
文摘Spiking neural networks(SNNs)utilize brain-like spatiotemporal spike encoding for simulating brain functions.Photonic SNN offers an ultrahigh speed and power efficiency platform for implementing high-performance neuromorphic computing.Here,we proposed a multi-synaptic photonic SNN,combining the modified remote supervised learning with delayweight co-training to achieve pattern classification.The impact of multi-synaptic connections and the robustness of the network were investigated through numerical simulations.In addition,the collaborative computing of algorithm and hardware was demonstrated based on a fabricated integrated distributed feedback laser with a saturable absorber(DFB-SA),where 10 different noisy digital patterns were successfully classified.A functional photonic SNN that far exceeds the scale limit of hardware integration was achieved based on time-division multiplexing,demonstrating the capability of hardware-algorithm co-computation.
基金Australian Research Council(DP220102152,DE220101085,FT200100590)Lee Lucas Chair in Physics+1 种基金Center for NanoScience,Ludwig-Maximilians Universität MünchenAustralian National Fabrication Facility。
文摘Orbital angular momentum(OAM)modes have emerged as a promising solution for enhancing the capacity of optical multiplexing systems,leveraging their theoretically unbounded set of orthogonal spatial modes.However,the generation and detection of OAM multiplexing signals are predominantly reliant on bulky optical components within complex optical setups.We introduce a compact solution for OAM information processing using laser-written glass chips,facilitating efficient multiplexing and demultiplexing of multiple OAM information channels.During the multiplexing process,OAM channels are managed via laser-scribed single-mode waveguides within a glass chip,with their modes converted using laser-written holograms on the side wall of the glass chip.The reciprocal process is employed for OAM demultiplexing.Our chips seamlessly interface with commercial optical fibers,ensuring compatibility with existing fiber-optic communication infrastructure.This work not only establishes,to our knowledge,a novel approach for OAM optical multiplexing but also underscores the potential of laser writing technology in advancing photonics and its practical applications in optical communications.
文摘In this study, tetrahedral amorphous carbon (ta-C) films with thicknesses between several 100 nm and several micrometers have been deposited onto polished tungsten carbide and steel substrates by pulsed laser deposition (PLD) using an excimer laser (248 nm wavelength). We investigate the optical properties (e.g. the refractive index (n) and extinction coefficient (k) in the visible and near-infrared wavelength range) of these layers in dependence of the used laser ablation fluence on the target. It is shown that n of ~2000 nm thick ta-C films can be tuned, depending on the sp3-content, between n = 2.5 and 2.8 at a wavelength of 632 nm. Besides of this k reduces with the sp3-content and is as low as 0.03 at sp3-contents of more than 75%. We proof that this gives the opportunity to prepare coating with tailored optical properties. Furthermore, it is shown that the ta-C films have low background fluorescence in the wavelengths range of 380 - 750 nm, which make this thin films attractive for certain optical, medical and biotechnological applications. We present for the first time that one possible application is the use in Lab-on-a-Chip-systems (LOC). Within these systems, the ultrasensitive detection of fluorescence markers and dyes is a challenge. In order to increase the signal-to-noise-ratio, a setup was developed, that used the specific optical properties of ta-C films produced by PLD. We used the ta-C film as an integrated reflector that combined low background fluorescence, a low reflectivity at the excitation wavelength and the high reflectivity at the emission wavelength. We prove that this setup improves the detection of fluorescence photons.
基金National Key Research and Development Program of China(2023YFB4604600)National Natural Science Foundation of China(12274133,12334014,12192251,12134001,12474378,12404379)+1 种基金Innovation Program for Quantum Science and Technology(2021ZD0301403)Fundamental Research Funds for the Central Universities,Engineering Research Center for Nanophotonics&Advanced Instrument,Ministry of Education,East China Normal University(2023nmc005)。
文摘Ytterbium ion(Yb^(3+))-doped lasers are widely used in precision machining and precision measurement fields because of their high efficiency and high power,which are primarily based on solid-state lasers and fiber lasers.Here,we demonstrate an on-chip Yb^(3+)-doped thin-film lithium niobate(Yb:TFLN)Fabry-Perot microcavity laser.We achieve single-frequency laser operation at 1030 and 1060 nm with a side-mode suppression ratio above 30 dB,an emission linewidth below 40 pm,and an output power up to 1.5 mW at 1060 nm and 0.3 mW at 1030 nm.In addition,using the electro-optic effect of lithium niobate,we achieve a laser tuning efficiency of 4 pm/V.This work opens the path to on-chip high-power and mode-locked ultrafast laser output.
