To enhance the quality factor and sensitivity of refractive index sensors,a feedback waveguide slot grating micro-ring resonator was proposed.An air-hole grating structure was introduced based on the slot micro-ring,u...To enhance the quality factor and sensitivity of refractive index sensors,a feedback waveguide slot grating micro-ring resonator was proposed.An air-hole grating structure was introduced based on the slot micro-ring,utilizing the reflection of the grating to achieve the electromagnetic-like induced transparency effect at different wavelengths.The high slope characteristics of the EIT-like effect enabled a higher quality factor and sensitivity.The transmission principle of the structure was analyzed using the transmission matrix method,and the transmission spectrum and mode field distribution were simulated using the finite-difference time-domain(FDTD)method,and the device structure parameters were adjusted for optimization.Simulation results show that the proposed structure achieves an EIT-like effect with a quality factor of 59267.5.In the analysis of refractive index sensing characteristics,the structure exhibits a sensitivity of 408.57 nm/RIU and a detection limit of 6.23×10^(-5) RIU.Therefore,the proposed structure achieved both a high quality factor and refractive index sensitivity,demonstrating excellent sensing performance for applications in environmental monitoring,biomedical fields,and other areas with broad market potential.展开更多
A plasmonics waveguide structure that consist of a non-through metal–insulator–metal(MIM)waveguide coupled with a D-shaped cavity was designed.And the transmission properties,magnetic field distribution,and refracti...A plasmonics waveguide structure that consist of a non-through metal–insulator–metal(MIM)waveguide coupled with a D-shaped cavity was designed.And the transmission properties,magnetic field distribution,and refractive index sensing functionality were simulated using the finite element method(FEM).A multi-Fano resonance phenomenon was clearly observable in the transmission spectra.The Fano resonances observed in the proposed structure arise from the interaction between the discrete states of the Dshaped resonant cavity and the continuum state of the non-through MIM waveguide.The influence of structural parameters on Fano resonance modulation was investigated through systematic parameter adjustments.Additionally,the refractive index sensing properties,based on the Fano resonance,were investigated by varying the refractive index of the MIM waveguide's insulator layer.A maximum sensitivity and FOM of 1155 RIU/nm and 40 were achieved,respectively.This research opens up new possibilities for designing and exploring high-sensitivity photonic devices,micro-sensors,and innovative on-chip sensing architectures for future applications.展开更多
This paper presents a photonic crystal(PhC)line-defect slow-light waveguide modified by resonant rings.We introduce resonant rings into the line defect,constructing a slow-light waveguide with high normalized delay ba...This paper presents a photonic crystal(PhC)line-defect slow-light waveguide modified by resonant rings.We introduce resonant rings into the line defect,constructing a slow-light waveguide with high normalized delay bandwidth product(NDBP)and low group velocity dispersion(GVD).We simulate,analyze,and optimize the structural parameters of this slow-light waveguide using the finite difference time domain(FDTD)method,theoretically achieving a maximum group index of 3.7,maximum bandwidth of 15.6 nm,and maximum NDBP of 0.4416 for slow-light effect.The resonant ring-modified PhC slow-light waveguide designed in this paper exhibits GVD lower than the order of 10^(−20)s^(2)/m over a normalized frequency range from 0.3554 to 0.4175.This study is expected to provide theoretical references for the study of slow-light buffering devices based on PhCs with high NDBP values.展开更多
To achieve high quality factor and high-sensitivity refractive index sensor,a slot micro-ring resonator(MRR)based on asymmetric Fabry-Perot(FP)cavity was proposed.The structure consisted of a pair of elliptical holes ...To achieve high quality factor and high-sensitivity refractive index sensor,a slot micro-ring resonator(MRR)based on asymmetric Fabry-Perot(FP)cavity was proposed.The structure consisted of a pair of elliptical holes to form an FP cavity and a microring resonator.The two different optical modes generated by the micro-ring resonator were destructively interfered to form a Fano line shape,which improved the system sensitivity while obtaining a higher quality factor and extinction ratio.The transmission principle of the structure was analyzed by the transfer matrix method.The transmission spectrum and mode field distribution of the proposed structure were simulated by the finite difference time domain(FDTD)method,and the key structural parameters affecting the Fano line shape in the device were optimized.The simulation results show that the quality factor of the device reached 22037.1,and the extinction ratio was 23.9 dB.By analyzing the refractive index sensing characteristics,the sensitivity of the structure was 354 nm·RIU−1,and the detection limit of the sensitivity was 2×10−4 RIU.Thus,the proposed compact asymmetric FP cavity slot micro-ring resonator has obvious advantages in sensing applications owing to its excellent performance.展开更多
The single photon scattering properties in a pair of waveguides coupled by a whispering-gallery resonator in- teracting with a semiconductor quantum dot are investigated theoretically. The two waveguides support four ...The single photon scattering properties in a pair of waveguides coupled by a whispering-gallery resonator in- teracting with a semiconductor quantum dot are investigated theoretically. The two waveguides support four possible ports for an incident single photon. The quantum dot is considered a V-type system. The incident direction-dependent single photon scattering properties are studied and equal-output probability from the four ports for a single photon incident is discussed. The influences of backscattering between the two modes of the whispering-gallery resonator for incident direction-dependent single photon scattering properties are also pre- sented.展开更多
This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal(HMIM) wave-guide, circular ring resonator(CRR) based dual-band band-pass filters with two transmission poles in bot...This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal(HMIM) wave-guide, circular ring resonator(CRR) based dual-band band-pass filters with two transmission poles in both pass-bands in the optical regime using coupled line feed. The transmission line characteristics of an HMIM waveguide, such as characteristic impedance(Z_(PV)), effective refractive index(n_(eff)) and propagation length(L_(spp)), have been obtained by using full wave simulation.展开更多
A single baffle metal–insulator–metal(MIM)waveguide coupled with a semi-circular cavity and a cross-shaped cavity is proposed based on the multiple Fano resonance characteristics of surface plasmon polaritons(SPPs)s...A single baffle metal–insulator–metal(MIM)waveguide coupled with a semi-circular cavity and a cross-shaped cavity is proposed based on the multiple Fano resonance characteristics of surface plasmon polaritons(SPPs)subwavelength structure.The isolated state formed by two resonators interferes with the wider continuous state mode formed by the metal baffle,forming Fano resonance that can independently be tuned into five different modes.The formation mechanism of Fano resonance is analyzed based on the multimode interference coupled mode theory(MICMT).The finite element method(FEM)and MICMT are used to simulate the transmission spectra of this structure and analyze the influence of structural parameters on the refractive index sensing characteristics.And the transmission responses calculated by the FEM simulation are consistent with the MICMT theoretical results very well.The results show that the figure of merit(FOM)can reach 193 and the ultra-high sensitivity is 1600 nm/RIU after the structure parameters have been optimized,and can provide theoretical basis for designing the high sensitive refractive index sensors based on SPPs waveguide for high-density photonic integration with excellent performance in the near future.展开更多
It is well known that the radiation efficiency of an acoustic dipole is very low, increasing the radiation efficiency of an acoustic dipole is a difficult task, especially in an ordinary waveguide.In addition, current...It is well known that the radiation efficiency of an acoustic dipole is very low, increasing the radiation efficiency of an acoustic dipole is a difficult task, especially in an ordinary waveguide.In addition, current acoustic superlenses all utilize in-phase sources to do the super-resolution imaging, it is almost impossible to realize super-resolution imaging of an acoustic dipole.In this paper, after using the Helmholtz resonator arrays(HRAs) which are placed at the upper and lower surfaces of the waveguide, we observe a large dipole radiation efficiency at the certain frequency, which gives a method to observe an acoustic dipole in the far field and offers a novel model which is promising to realize the superlens with a source of an acoustic dipole.We discuss how the arrangement of HRAs affects the transmission of the acoustic dipole.展开更多
A tunable superconducting half-wavelength coplanar waveguide resonator （CPWR） with Nb parallel nanowires - 300 nm in width embedded in the center conductor was designed, fabricated, and measured. The frequency shift...A tunable superconducting half-wavelength coplanar waveguide resonator （CPWR） with Nb parallel nanowires - 300 nm in width embedded in the center conductor was designed, fabricated, and measured. The frequency shift and the amplitude attenuation of the resonance peak under irradiation of 404-nm pulse laser were observed with different light powers at 4.2 K. The RF power supplied to such a CPWR can serve as current bias, which will affect the light response of the resonator.展开更多
We propose a scheme for transferring entanglement through two independent arrays of coupled resonator waveguides, where a three-level atom is embedded in each resonator. We investigate the entanglement dynamics of the...We propose a scheme for transferring entanglement through two independent arrays of coupled resonator waveguides, where a three-level atom is embedded in each resonator. We investigate the entanglement dynamics of the transferred state. The influence of initial states and applied lasers on the entanglement sudden death phenomenon is also discussed. Furthermore, we study the dynamics of pairwise quantum correlations measured by the quantum discord.展开更多
A nonlinear integrated optical platform that allows the fabrication of waveguide circuits with different material composition,and at small dimensions,offers advantages in terms of field enhancement and increased inter...A nonlinear integrated optical platform that allows the fabrication of waveguide circuits with different material composition,and at small dimensions,offers advantages in terms of field enhancement and increased interaction length,thereby facilitating the observation of nonlinear optics effects at a much lower power level.To enhance the nonlinearity of the conventional waveguide structure,in this work,we propose and demonstrate a microstructured waveguide where silicon rich layer is embedded in the core of the conventional waveguide in order to increase its nonlinearity.By embedding a 20 nm thin film of silicon nanocrystal(Si-nc),we achieve a twofold increase of the nonlinear parameter,γ.The linear relationship between the fourwave mixing conversion efficiency and pump power reveals the negligible nonlinear absorption and small dispersion in the micro-ring resonators.This simple approach of embedding an ultra-thin Si-nc layer into conventional high-index doped silica dramatically increases its nonlinear performance,and could potentially find applications in all-optical processing functions.展开更多
Single photon transport properties in a one-dimensional array of coupled microcavities waveguide coupled to a whispering-gallery resonator interacting with aΛ-type system are theoretically investigated.The calculatio...Single photon transport properties in a one-dimensional array of coupled microcavities waveguide coupled to a whispering-gallery resonator interacting with aΛ-type system are theoretically investigated.The calculations reveal that the transport properties of single photons with arbitrary energy can be controlled by varying the Rabi frequency and detuning the control optical field.This phenomenon can be used for controllable optical switching.展开更多
We theoretically investigate the single photon transport in a coupled resonator waveguide embedded in a semiconductor quantum dot with a V-type system.The transmission and reflection amplitudes are obtained by using a...We theoretically investigate the single photon transport in a coupled resonator waveguide embedded in a semiconductor quantum dot with a V-type system.The transmission and reflection amplitudes are obtained by using a discrete coordinates approach.It is shown that the photon transport properties can be controlled by the energy detuning between the two excited states of the V-type system,and the coupling strength between the photon and the V-type system.We also compare the single photon transport properties in the waveguide with sinusoidal and linear dispersion relations.展开更多
In this paper, bendloss characteristics of an optical fibre are investigated in detail, and the results show that the resonator with a smaller ring radius, wider free spectrum range （FSR）, higher fineness （f） and ...In this paper, bendloss characteristics of an optical fibre are investigated in detail, and the results show that the resonator with a smaller ring radius, wider free spectrum range （FSR）, higher fineness （f） and quality-factor （Q） can be achieved by using microfibres. Based on the improved fused taper technique, a high-quality microfibre with 5 ttm radius has been fabricated, and an all-fibre micro-ring resonator with a radius of only 500μm is realized using self-coiling coupling method. The good-resonant characteristic makes the all-fibre device be expected to avoid bendloss and connection loss associated with planar waveguide integration.展开更多
We investigate theoretically the single-photon scattering by a A-type three-level system interacting with a whispering-gallery-type resonator which is coupled to a one-dimensional waveguide by full quantum-mechanical ...We investigate theoretically the single-photon scattering by a A-type three-level system interacting with a whispering-gallery-type resonator which is coupled to a one-dimensional waveguide by full quantum-mechanical approach. The single-photon transmission amplitude and reflection amplitude are obtained exactly via real-space approach. The single-photon transport properties controlling by classic optical field are discussed. The critical coupling condition in the coupled waveguide-whispering-gallery resonator-atom with three-level system is also analyzed.展开更多
A four-channel integrated optical wavelength de-multiplexer is experimentally illustrated on a silicon-on-insulator （SO1） substrate. With the aid of cascaded micro-ring resonators, the whole performance of the wavel...A four-channel integrated optical wavelength de-multiplexer is experimentally illustrated on a silicon-on-insulator （SO1） substrate. With the aid of cascaded micro-ring resonators, the whole performance of the wavelength de- multiplexer is improved, such as 3 dB bandwidth and channel crosstalk. Based on the transform matrix theory, a four-channel wavelength de-multiplexer with average channel spacing 4.5±0.5 nm （3 dB bandwidth - 2 ± 0.5 nm） is demonstrated at telecommunication bands. For each channel, the extinction at the adjacent channel is below -39dB and the out-of-band rejection ratio is up to 40dB. The channel dropping loss is below 5dB in the five FSR spectral response periods （near 100 nm）.展开更多
Developing a convenient method that can be routinely applied for ascertaining proportions of different vegetable oils employed in commercial blended edible oils remains a significant challenge.We address this issue by...Developing a convenient method that can be routinely applied for ascertaining proportions of different vegetable oils employed in commercial blended edible oils remains a significant challenge.We address this issue by proposing a novel method for detecting volume fraction of different oils based on the fact that these oils are optically transparent and have slightly different indices of refraction at a given temperature and wavelength.Accordingly,we develop a highly sensitive sensor for measuring the index of refraction of oil blends based on Fano resonance spectra obtained using a metal-insulatormetal(MIM)waveguide structure comprising a gapped straight waveguide coupled with two L-shaped resonators.The index of refraction sensitivity and figure of merit of the structure are calculated based on modeling using the finite element method,and the waveguide structure is accordingly optimized by adjusting the different geometric parameters to achieve a high-quality Fano resonance spectrum.The optimized structure achieves an ultra-high refractive index sensitivity of 770 nm/RIU in terms of a refractive index unit(RIU)of 1.Moreover,a highly stable linear relationship is obtained between the refractive index of mixed edible oils and the resonance wavelength.Experimental results demonstrate that the proposed structure can detect slight changes in the volume fractions of the components in blended oils.展开更多
Based on the measurement of the contrast ratios of the transmission spectra from the throughput and drop ports of ring resonator, an efficient method is proposed to extract the coupling ratio and round-trip loss of th...Based on the measurement of the contrast ratios of the transmission spectra from the throughput and drop ports of ring resonator, an efficient method is proposed to extract the coupling ratio and round-trip loss of the integrated optical waveguide ring resonator. The parameters of a racetrack resonator prepared by ion-exchange technique in K9 optical glass substrate are examined, which demonstrates the validity of this method. The accuracy and applicable range of this method are also discussed.展开更多
A high-sensitivity plasmonic refractive-index sensor based on the asymmetrical coupling of two metal-insulator- metal waveguides with a nanodisk resonator is proposed and simulated in the finite-difference time domain...A high-sensitivity plasmonic refractive-index sensor based on the asymmetrical coupling of two metal-insulator- metal waveguides with a nanodisk resonator is proposed and simulated in the finite-difference time domain. Both analytic and simulated results show that the resonance wavelengths of the sensor have an approximate linear relationship with the refractive index of the materials which are filled into the slit waveguides and the disk- shaped resonator. The working mechanism of this sensor is exactly due to the linear relationship, based on which tile refractive index of the materials unknown can be obtained from the detection of the resonance wavelength. The measurement sensitivity can reach as high as 6.45 × 10-7, which is nearly five times higher than the results reported in the recent literature [Opt. Commun. 300 （2013） 265]. With an optimum design, the sensing value can be further improved, and it can be widely applied into the biological sensing. Tile sensor working for temperature sensing is also analyzed.展开更多
To improve the integration of Fano devices,we design a T-shaped waveguide coupling micro-ring resonator(MRR)structure to achieve a single cavity with Fano resonance in the whole spectral bands.The mathematical relatio...To improve the integration of Fano devices,we design a T-shaped waveguide coupling micro-ring resonator(MRR)structure to achieve a single cavity with Fano resonance in the whole spectral bands.The mathematical relationship between the phase factor,the coupling coefficient of the bus waveguide,and the Fano resonance slope extinction ratio(ER)is established.The electron beam exposure process is used to obtain a device with an insertion loss of~3 dB.The maximum ER of the Fano lineshape exceeds 15 dB,and the slope ratio(SR)is 251.3 dB/nm.This design improves the compactness of the Fano resonant device.展开更多
基金supported by Natural Science Foundation of Gansu Province(NO.21JR7RA289)。
文摘To enhance the quality factor and sensitivity of refractive index sensors,a feedback waveguide slot grating micro-ring resonator was proposed.An air-hole grating structure was introduced based on the slot micro-ring,utilizing the reflection of the grating to achieve the electromagnetic-like induced transparency effect at different wavelengths.The high slope characteristics of the EIT-like effect enabled a higher quality factor and sensitivity.The transmission principle of the structure was analyzed using the transmission matrix method,and the transmission spectrum and mode field distribution were simulated using the finite-difference time-domain(FDTD)method,and the device structure parameters were adjusted for optimization.Simulation results show that the proposed structure achieves an EIT-like effect with a quality factor of 59267.5.In the analysis of refractive index sensing characteristics,the structure exhibits a sensitivity of 408.57 nm/RIU and a detection limit of 6.23×10^(-5) RIU.Therefore,the proposed structure achieved both a high quality factor and refractive index sensitivity,demonstrating excellent sensing performance for applications in environmental monitoring,biomedical fields,and other areas with broad market potential.
文摘A plasmonics waveguide structure that consist of a non-through metal–insulator–metal(MIM)waveguide coupled with a D-shaped cavity was designed.And the transmission properties,magnetic field distribution,and refractive index sensing functionality were simulated using the finite element method(FEM).A multi-Fano resonance phenomenon was clearly observable in the transmission spectra.The Fano resonances observed in the proposed structure arise from the interaction between the discrete states of the Dshaped resonant cavity and the continuum state of the non-through MIM waveguide.The influence of structural parameters on Fano resonance modulation was investigated through systematic parameter adjustments.Additionally,the refractive index sensing properties,based on the Fano resonance,were investigated by varying the refractive index of the MIM waveguide's insulator layer.A maximum sensitivity and FOM of 1155 RIU/nm and 40 were achieved,respectively.This research opens up new possibilities for designing and exploring high-sensitivity photonic devices,micro-sensors,and innovative on-chip sensing architectures for future applications.
基金supported by the Graduate Student Innovation Fund of Xi’an Shiyou University(No.YCS21211087).
文摘This paper presents a photonic crystal(PhC)line-defect slow-light waveguide modified by resonant rings.We introduce resonant rings into the line defect,constructing a slow-light waveguide with high normalized delay bandwidth product(NDBP)and low group velocity dispersion(GVD).We simulate,analyze,and optimize the structural parameters of this slow-light waveguide using the finite difference time domain(FDTD)method,theoretically achieving a maximum group index of 3.7,maximum bandwidth of 15.6 nm,and maximum NDBP of 0.4416 for slow-light effect.The resonant ring-modified PhC slow-light waveguide designed in this paper exhibits GVD lower than the order of 10^(−20)s^(2)/m over a normalized frequency range from 0.3554 to 0.4175.This study is expected to provide theoretical references for the study of slow-light buffering devices based on PhCs with high NDBP values.
基金supported by Natural Science Foundation of Gansu Province(No.22JR5RA320).
文摘To achieve high quality factor and high-sensitivity refractive index sensor,a slot micro-ring resonator(MRR)based on asymmetric Fabry-Perot(FP)cavity was proposed.The structure consisted of a pair of elliptical holes to form an FP cavity and a microring resonator.The two different optical modes generated by the micro-ring resonator were destructively interfered to form a Fano line shape,which improved the system sensitivity while obtaining a higher quality factor and extinction ratio.The transmission principle of the structure was analyzed by the transfer matrix method.The transmission spectrum and mode field distribution of the proposed structure were simulated by the finite difference time domain(FDTD)method,and the key structural parameters affecting the Fano line shape in the device were optimized.The simulation results show that the quality factor of the device reached 22037.1,and the extinction ratio was 23.9 dB.By analyzing the refractive index sensing characteristics,the sensitivity of the structure was 354 nm·RIU−1,and the detection limit of the sensitivity was 2×10−4 RIU.Thus,the proposed compact asymmetric FP cavity slot micro-ring resonator has obvious advantages in sensing applications owing to its excellent performance.
基金Supported by the National Natural Science Foundation of China under Grant No 11105001the Anhui Provincial Natural Science Foundation under Grant Nos 1408085QA22 and 1608085MA09
文摘The single photon scattering properties in a pair of waveguides coupled by a whispering-gallery resonator in- teracting with a semiconductor quantum dot are investigated theoretically. The two waveguides support four possible ports for an incident single photon. The quantum dot is considered a V-type system. The incident direction-dependent single photon scattering properties are studied and equal-output probability from the four ports for a single photon incident is discussed. The influences of backscattering between the two modes of the whispering-gallery resonator for incident direction-dependent single photon scattering properties are also pre- sented.
文摘This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal(HMIM) wave-guide, circular ring resonator(CRR) based dual-band band-pass filters with two transmission poles in both pass-bands in the optical regime using coupled line feed. The transmission line characteristics of an HMIM waveguide, such as characteristic impedance(Z_(PV)), effective refractive index(n_(eff)) and propagation length(L_(spp)), have been obtained by using full wave simulation.
基金National Natural Science Foundation of China(Grant Nos.61367005 and 61865008)the Natural Science Foundation of Gansu Province,China(Grant No.17JR5RA078).
文摘A single baffle metal–insulator–metal(MIM)waveguide coupled with a semi-circular cavity and a cross-shaped cavity is proposed based on the multiple Fano resonance characteristics of surface plasmon polaritons(SPPs)subwavelength structure.The isolated state formed by two resonators interferes with the wider continuous state mode formed by the metal baffle,forming Fano resonance that can independently be tuned into five different modes.The formation mechanism of Fano resonance is analyzed based on the multimode interference coupled mode theory(MICMT).The finite element method(FEM)and MICMT are used to simulate the transmission spectra of this structure and analyze the influence of structural parameters on the refractive index sensing characteristics.And the transmission responses calculated by the FEM simulation are consistent with the MICMT theoretical results very well.The results show that the figure of merit(FOM)can reach 193 and the ultra-high sensitivity is 1600 nm/RIU after the structure parameters have been optimized,and can provide theoretical basis for designing the high sensitive refractive index sensors based on SPPs waveguide for high-density photonic integration with excellent performance in the near future.
基金Project supported by the National Key R&D Program of China(Grant No.2017YFA0303702)State Key Program of the National Natural Science Foundation of China(Grant No.11834008)+3 种基金the National Natural Science Foundation of China(Grant No.11774167)State Key Laboratory of Acoustics,Chinese Academy of Sciences(Grant No.SKLA201809)Key Laboratory of Underwater Acoustic Environment,Chinese Academy of Sciences(Grant No.SSHJ-KFKT-1701)AQSIQ Technology R&D Program,China(Grant No.2017QK125)
文摘It is well known that the radiation efficiency of an acoustic dipole is very low, increasing the radiation efficiency of an acoustic dipole is a difficult task, especially in an ordinary waveguide.In addition, current acoustic superlenses all utilize in-phase sources to do the super-resolution imaging, it is almost impossible to realize super-resolution imaging of an acoustic dipole.In this paper, after using the Helmholtz resonator arrays(HRAs) which are placed at the upper and lower surfaces of the waveguide, we observe a large dipole radiation efficiency at the certain frequency, which gives a method to observe an acoustic dipole in the far field and offers a novel model which is promising to realize the superlens with a source of an acoustic dipole.We discuss how the arrangement of HRAs affects the transmission of the acoustic dipole.
基金Project supported by the National Basic Research Program of China(Grant Nos.2011CB922104 and 2011CBA00200)the National Natural Science Foundation of China(Grant No.11474154)+1 种基金the Jiangsu Natural Science Fund for Distinguished Young Scholars(Grant No.BK2012013)a Doctoral Program(Grant No.20120091110030)
文摘A tunable superconducting half-wavelength coplanar waveguide resonator （CPWR） with Nb parallel nanowires - 300 nm in width embedded in the center conductor was designed, fabricated, and measured. The frequency shift and the amplitude attenuation of the resonance peak under irradiation of 404-nm pulse laser were observed with different light powers at 4.2 K. The RF power supplied to such a CPWR can serve as current bias, which will affect the light response of the resonator.
基金Project supported by the National Natural Science Foundation of China(Grant No.10774131)
文摘We propose a scheme for transferring entanglement through two independent arrays of coupled resonator waveguides, where a three-level atom is embedded in each resonator. We investigate the entanglement dynamics of the transferred state. The influence of initial states and applied lasers on the entanglement sudden death phenomenon is also discussed. Furthermore, we study the dynamics of pairwise quantum correlations measured by the quantum discord.
基金the Research Grants Council,University Grants Committee(GRF 11213618)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB24030300).
文摘A nonlinear integrated optical platform that allows the fabrication of waveguide circuits with different material composition,and at small dimensions,offers advantages in terms of field enhancement and increased interaction length,thereby facilitating the observation of nonlinear optics effects at a much lower power level.To enhance the nonlinearity of the conventional waveguide structure,in this work,we propose and demonstrate a microstructured waveguide where silicon rich layer is embedded in the core of the conventional waveguide in order to increase its nonlinearity.By embedding a 20 nm thin film of silicon nanocrystal(Si-nc),we achieve a twofold increase of the nonlinear parameter,γ.The linear relationship between the fourwave mixing conversion efficiency and pump power reveals the negligible nonlinear absorption and small dispersion in the micro-ring resonators.This simple approach of embedding an ultra-thin Si-nc layer into conventional high-index doped silica dramatically increases its nonlinear performance,and could potentially find applications in all-optical processing functions.
文摘Single photon transport properties in a one-dimensional array of coupled microcavities waveguide coupled to a whispering-gallery resonator interacting with aΛ-type system are theoretically investigated.The calculations reveal that the transport properties of single photons with arbitrary energy can be controlled by varying the Rabi frequency and detuning the control optical field.This phenomenon can be used for controllable optical switching.
文摘We theoretically investigate the single photon transport in a coupled resonator waveguide embedded in a semiconductor quantum dot with a V-type system.The transmission and reflection amplitudes are obtained by using a discrete coordinates approach.It is shown that the photon transport properties can be controlled by the energy detuning between the two excited states of the V-type system,and the coupling strength between the photon and the V-type system.We also compare the single photon transport properties in the waveguide with sinusoidal and linear dispersion relations.
基金Project supported by the National Natural Science Foundation of China(Grant No60607001)the Natural Science Foundation of Beijing,China(Grant No4052023)the Talents of Beijing Jiaotong University,Beijing,China(Grant No2007RC015)
文摘In this paper, bendloss characteristics of an optical fibre are investigated in detail, and the results show that the resonator with a smaller ring radius, wider free spectrum range （FSR）, higher fineness （f） and quality-factor （Q） can be achieved by using microfibres. Based on the improved fused taper technique, a high-quality microfibre with 5 ttm radius has been fabricated, and an all-fibre micro-ring resonator with a radius of only 500μm is realized using self-coiling coupling method. The good-resonant characteristic makes the all-fibre device be expected to avoid bendloss and connection loss associated with planar waveguide integration.
基金＊Supported by National Natural Science Foundation of China under Grant Nos. 10874134, 11004001, and 10947115 and Anhui Province for Young Teachers Foundation under Crant No. 2010SQRL037ZD
文摘We investigate theoretically the single-photon scattering by a A-type three-level system interacting with a whispering-gallery-type resonator which is coupled to a one-dimensional waveguide by full quantum-mechanical approach. The single-photon transmission amplitude and reflection amplitude are obtained exactly via real-space approach. The single-photon transport properties controlling by classic optical field are discussed. The critical coupling condition in the coupled waveguide-whispering-gallery resonator-atom with three-level system is also analyzed.
基金Supported by the National High Technology Research and Development Program of China under Grant No 2015AA016904the National Key Research and Development Plan of China under Grant No 2016YFB0402502the National Natural Science Foundation of China under Grant No 61275065
文摘A four-channel integrated optical wavelength de-multiplexer is experimentally illustrated on a silicon-on-insulator （SO1） substrate. With the aid of cascaded micro-ring resonators, the whole performance of the wavelength de- multiplexer is improved, such as 3 dB bandwidth and channel crosstalk. Based on the transform matrix theory, a four-channel wavelength de-multiplexer with average channel spacing 4.5±0.5 nm （3 dB bandwidth - 2 ± 0.5 nm） is demonstrated at telecommunication bands. For each channel, the extinction at the adjacent channel is below -39dB and the out-of-band rejection ratio is up to 40dB. The channel dropping loss is below 5dB in the five FSR spectral response periods （near 100 nm）.
基金supported by the National Natural Science Foundation of China(Grant No.51965007)the“One thousand Young and Middle-Aged College and University Backbone Teachers Cultivation Program”of Guangxi,China(Grant No.2019)。
文摘Developing a convenient method that can be routinely applied for ascertaining proportions of different vegetable oils employed in commercial blended edible oils remains a significant challenge.We address this issue by proposing a novel method for detecting volume fraction of different oils based on the fact that these oils are optically transparent and have slightly different indices of refraction at a given temperature and wavelength.Accordingly,we develop a highly sensitive sensor for measuring the index of refraction of oil blends based on Fano resonance spectra obtained using a metal-insulatormetal(MIM)waveguide structure comprising a gapped straight waveguide coupled with two L-shaped resonators.The index of refraction sensitivity and figure of merit of the structure are calculated based on modeling using the finite element method,and the waveguide structure is accordingly optimized by adjusting the different geometric parameters to achieve a high-quality Fano resonance spectrum.The optimized structure achieves an ultra-high refractive index sensitivity of 770 nm/RIU in terms of a refractive index unit(RIU)of 1.Moreover,a highly stable linear relationship is obtained between the refractive index of mixed edible oils and the resonance wavelength.Experimental results demonstrate that the proposed structure can detect slight changes in the volume fractions of the components in blended oils.
基金National Natural Science Foundation of China(60577014)Young Teacher Cultivation Foundation of Dalian University of Technology(893210) Doctor Start-up Foundation of Dalian University of Technology(893322)
文摘Based on the measurement of the contrast ratios of the transmission spectra from the throughput and drop ports of ring resonator, an efficient method is proposed to extract the coupling ratio and round-trip loss of the integrated optical waveguide ring resonator. The parameters of a racetrack resonator prepared by ion-exchange technique in K9 optical glass substrate are examined, which demonstrates the validity of this method. The accuracy and applicable range of this method are also discussed.
基金Supported by the National Natural Science Foundation of China under Grant No 61275059
文摘A high-sensitivity plasmonic refractive-index sensor based on the asymmetrical coupling of two metal-insulator- metal waveguides with a nanodisk resonator is proposed and simulated in the finite-difference time domain. Both analytic and simulated results show that the resonance wavelengths of the sensor have an approximate linear relationship with the refractive index of the materials which are filled into the slit waveguides and the disk- shaped resonator. The working mechanism of this sensor is exactly due to the linear relationship, based on which tile refractive index of the materials unknown can be obtained from the detection of the resonance wavelength. The measurement sensitivity can reach as high as 6.45 × 10-7, which is nearly five times higher than the results reported in the recent literature [Opt. Commun. 300 （2013） 265]. With an optimum design, the sensing value can be further improved, and it can be widely applied into the biological sensing. Tile sensor working for temperature sensing is also analyzed.
基金supported by the State Grid Zhejiang Electric Power Corporation Information Telecommunication Branch(No.B311XT21004G)the 111 Project of China(No.D17021)+1 种基金the National Natural Science Foundation of China(No.61903042)the Beijing Natural Science Foundation(No.4214081)。
文摘To improve the integration of Fano devices,we design a T-shaped waveguide coupling micro-ring resonator(MRR)structure to achieve a single cavity with Fano resonance in the whole spectral bands.The mathematical relationship between the phase factor,the coupling coefficient of the bus waveguide,and the Fano resonance slope extinction ratio(ER)is established.The electron beam exposure process is used to obtain a device with an insertion loss of~3 dB.The maximum ER of the Fano lineshape exceeds 15 dB,and the slope ratio(SR)is 251.3 dB/nm.This design improves the compactness of the Fano resonant device.
