In this paper, a sinusoidal phase-modulating Fabry-Perot interferometer is proposed to measure angular displacement. The usefulness of the interferometer is demonstrated by simulations and experiments.
A signal processing method of realizing a large-range displacement measurement in a sinusoidal phase- modulating laser diode interferometer is proposed. The method of obtaining the dynamic value of the effective sinus...A signal processing method of realizing a large-range displacement measurement in a sinusoidal phase- modulating laser diode interferometer is proposed. The method of obtaining the dynamic value of the effective sinusoidal phase-modulating depth is detailed, and the residual amplitude modulation is also taken into account. Numerical simulations and experiments are carried out to compare this method with the traditional one. We prove that, with this method, the sinusoidal phase-modulating laser diode interferometer can realize a centimeter-level displacement measurement range with high precision, which is much better than the traditional method.展开更多
Phase-modulated metasurfaces that can implement the independent manipulation of co-and cross-polarized output waves under circularly polarized[CP]incidence have been proposed.With this,we introduce one particular meta...Phase-modulated metasurfaces that can implement the independent manipulation of co-and cross-polarized output waves under circularly polarized[CP]incidence have been proposed.With this,we introduce one particular metasurface composed of meta-atoms with a phase difference of 2π/3 to generate specific elliptically polarized waves under various polarized incidences.Furthermore,a metasurface composed of these above meta-atoms and the meta-atoms with a phase difference of π/3 arranged in a certain rule can realize polarization conversion function between linearly polarized and CP states.The designs shed new light on multifarious optical devices and may further promote the development of metasurface polarization optics.展开更多
The Kerr nonlinearity in two-dimensional(2D)nanomaterials is emerging as an appealing and intriguing research area due to their prominent light processing,modulation,and manipulation abilities.In this contribution,2D ...The Kerr nonlinearity in two-dimensional(2D)nanomaterials is emerging as an appealing and intriguing research area due to their prominent light processing,modulation,and manipulation abilities.In this contribution,2D black arsenic-phosphorus(B-AsP)nanosheets(NSs)were applied in nonlinear photonic devices based on spatial self-phase modula-tion(SSPM)method.By applying the Kerr nonlinearity in 2D B-AsP,an all-optical phase-modulated system is proposed to realize the functions of“on”and“off”in all-optical switching.By using the same all-optical phase-modulated system,another optical logic gate is proposed,and the logical“or”function is obtained based on the 2D B-AsP NSs dispersions.Moreover,by using the SSPM method,a 2D B-AsP/SnS_(2) hybrid structure is fabricated,and the result illustrates that the hybrid structure possesses the ability of the unidirectional nonlinear excitation,which helps in obtaining the function of spatial asymmetric light propagation.This function is considered an important prerequisite for the realization of diode functionalization,which is believed to be a factor in important basis for the design of isolators as well.The initial investig-ations indicate that 2D B-AsP is applicable for designing optical logical devices,which can be considered as an import-ant development in all-optical information processing.展开更多
Extended target detection performance can be enhanced by using phase-modulated waveform designs in band-limited radar systems. Unlike waveforms designed for the total energy constraint, phase-modulated waveforms can f...Extended target detection performance can be enhanced by using phase-modulated waveform designs in band-limited radar systems. Unlike waveforms designed for the total energy constraint, phase-modulated waveforms can fully exploit the transmit power in the pulse duration, which is more suit- able for practical radar systems. An alternating iterative algorithm was developed to optimize the phase-modulated baseband waveform by maximizing the signal-to-noise ratio （SNR） at the receiver filter output. The output SNR increases continuously with the number of iterations and the algorithm is guaran- teed to converge. Simulations validate the effectiveness of this approach. The waveforms designed by this method outperform other commonly used waveforms for extended target detection.展开更多
The absorption spectrum and the incoherent fluorescence spectrum of the lower transition in an E-configuration threelevel atomic system driven by a pair of bichromatic fields is investigated. The transmission of the a...The absorption spectrum and the incoherent fluorescence spectrum of the lower transition in an E-configuration threelevel atomic system driven by a pair of bichromatic fields is investigated. The transmission of the absorption profile from a multipeaked feature to a single-peak feature is identified. Adjusting the relative phase between the two driving fields, the splitting effects of the spectral peaks occur both in the fluorescence and the absorption spectra. Furthermore, phase modulating can dramatically lead to a great suppression of the amplitudes ofthe whole absorption spectrum. Physically, this effect is attributed to the phase-sensitive nature of the populations and coherence between the atomic states of the system.展开更多
An injection-Locked divider(ILD)can provide good synchronization at lower inputsignal to noise ratio,which is its advantage over other types of divider.The general expressionof phase equation and equivalent model are ...An injection-Locked divider(ILD)can provide good synchronization at lower inputsignal to noise ratio,which is its advantage over other types of divider.The general expressionof phase equation and equivalent model are presented for the ILD with an input additive noise.In the absence of noise the performance of the phase-modulated signal through the ILD andsynchronous ranges of the ILD are given.The effects of the additive noise on the ILD arediscuued.The injection-locked amplifier(ILA)is only a particular case in which n=1,thereforethe given results arc applicable to the ILA.展开更多
文摘In this paper, a sinusoidal phase-modulating Fabry-Perot interferometer is proposed to measure angular displacement. The usefulness of the interferometer is demonstrated by simulations and experiments.
基金supported by the National Natural Science Foundation of China under Grant No.51475262
文摘A signal processing method of realizing a large-range displacement measurement in a sinusoidal phase- modulating laser diode interferometer is proposed. The method of obtaining the dynamic value of the effective sinusoidal phase-modulating depth is detailed, and the residual amplitude modulation is also taken into account. Numerical simulations and experiments are carried out to compare this method with the traditional one. We prove that, with this method, the sinusoidal phase-modulating laser diode interferometer can realize a centimeter-level displacement measurement range with high precision, which is much better than the traditional method.
基金This work was supported by the National Natural Science Foundation of China(Nos.61675147,61735010,and 91838301)National Key Research and Development Program of China(No.2017YFA0700202).
文摘Phase-modulated metasurfaces that can implement the independent manipulation of co-and cross-polarized output waves under circularly polarized[CP]incidence have been proposed.With this,we introduce one particular metasurface composed of meta-atoms with a phase difference of 2π/3 to generate specific elliptically polarized waves under various polarized incidences.Furthermore,a metasurface composed of these above meta-atoms and the meta-atoms with a phase difference of π/3 arranged in a certain rule can realize polarization conversion function between linearly polarized and CP states.The designs shed new light on multifarious optical devices and may further promote the development of metasurface polarization optics.
基金supports from the National Natural Science Foundation of China(NSFC)(61435010 and 21773168)the Science and Technique Planning Project of Guangdong Province(Grant No.2016B050501005)+1 种基金the Science and Technology Innovation Commission of Shenzhen(JCYJ20170302153323978 and JCYJ201704101719588539)the Science and Technology Development Fund(No.007/2017/A1 and132/2017/A3),Ma-cao SAR,China.
文摘The Kerr nonlinearity in two-dimensional(2D)nanomaterials is emerging as an appealing and intriguing research area due to their prominent light processing,modulation,and manipulation abilities.In this contribution,2D black arsenic-phosphorus(B-AsP)nanosheets(NSs)were applied in nonlinear photonic devices based on spatial self-phase modula-tion(SSPM)method.By applying the Kerr nonlinearity in 2D B-AsP,an all-optical phase-modulated system is proposed to realize the functions of“on”and“off”in all-optical switching.By using the same all-optical phase-modulated system,another optical logic gate is proposed,and the logical“or”function is obtained based on the 2D B-AsP NSs dispersions.Moreover,by using the SSPM method,a 2D B-AsP/SnS_(2) hybrid structure is fabricated,and the result illustrates that the hybrid structure possesses the ability of the unidirectional nonlinear excitation,which helps in obtaining the function of spatial asymmetric light propagation.This function is considered an important prerequisite for the realization of diode functionalization,which is believed to be a factor in important basis for the design of isolators as well.The initial investig-ations indicate that 2D B-AsP is applicable for designing optical logical devices,which can be considered as an import-ant development in all-optical information processing.
基金Supported by the National Natural Science Foundation of China(No. 60901057)the National Key Basic Research and Devel-opment (973) Program of China (No. 2010CB731901)
文摘Extended target detection performance can be enhanced by using phase-modulated waveform designs in band-limited radar systems. Unlike waveforms designed for the total energy constraint, phase-modulated waveforms can fully exploit the transmit power in the pulse duration, which is more suit- able for practical radar systems. An alternating iterative algorithm was developed to optimize the phase-modulated baseband waveform by maximizing the signal-to-noise ratio （SNR） at the receiver filter output. The output SNR increases continuously with the number of iterations and the algorithm is guaran- teed to converge. Simulations validate the effectiveness of this approach. The waveforms designed by this method outperform other commonly used waveforms for extended target detection.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61008016, 10647008, and 50971099)the Natural Science Basis Research Plan in Shaanxi Province of China (Grant No. 2010JQ1002)+1 种基金the Education Department of Shaanxi Province, China (Grant Nos. 09JK752 and 11JK0550)the Doctoral Program Foundation of Institutions of Higher Education of China (Grant No. 20106101120020)
文摘The absorption spectrum and the incoherent fluorescence spectrum of the lower transition in an E-configuration threelevel atomic system driven by a pair of bichromatic fields is investigated. The transmission of the absorption profile from a multipeaked feature to a single-peak feature is identified. Adjusting the relative phase between the two driving fields, the splitting effects of the spectral peaks occur both in the fluorescence and the absorption spectra. Furthermore, phase modulating can dramatically lead to a great suppression of the amplitudes ofthe whole absorption spectrum. Physically, this effect is attributed to the phase-sensitive nature of the populations and coherence between the atomic states of the system.
文摘An injection-Locked divider(ILD)can provide good synchronization at lower inputsignal to noise ratio,which is its advantage over other types of divider.The general expressionof phase equation and equivalent model are presented for the ILD with an input additive noise.In the absence of noise the performance of the phase-modulated signal through the ILD andsynchronous ranges of the ILD are given.The effects of the additive noise on the ILD arediscuued.The injection-locked amplifier(ILA)is only a particular case in which n=1,thereforethe given results arc applicable to the ILA.
