In this paper, we propose a deterministic quantum communication protocol using weak coherent states and pulsed homodyne detection. In this protocol, the communication parties exchange their secret information determin...In this paper, we propose a deterministic quantum communication protocol using weak coherent states and pulsed homodyne detection. In this protocol, the communication parties exchange their secret information deterministicaJly in two rounds. The devices and efficiency of the protocol are discussed respectively. We also show the security of the protocol against intercept-resend and Trojan-Horse eavesdropping attacks.展开更多
Squeezed states belong to the most prominent non-classical resources.They have compelling applications in precise measurement, quantum computation, and detection.Here, we report on the direct measurement of 13.8 d B s...Squeezed states belong to the most prominent non-classical resources.They have compelling applications in precise measurement, quantum computation, and detection.Here, we report on the direct measurement of 13.8 d B squeezed vacuum states by improving the interference efficiency and gain of balanced homodyne detection.By employing an auxiliary laser beam, the homodyne visibility is increased to 99.8%.The equivalent loss of the electronic noise is reduced to 0.05% by integrating a junction field-effect transistor(JFET) buffering input and another JFET bootstrap structure in the balanced homodyne detector.展开更多
We propose an optical tensor core(OTC) architecture for neural network training. The key computational components of the OTC are the arrayed optical dot-product units(DPUs). The homodyne-detection-based DPUs can condu...We propose an optical tensor core(OTC) architecture for neural network training. The key computational components of the OTC are the arrayed optical dot-product units(DPUs). The homodyne-detection-based DPUs can conduct the essential computational work of neural network training, i.e., matrix-matrix multiplication. Dual-layer waveguide topology is adopted to feed data into these DPUs with ultra-low insertion loss and cross talk. Therefore, the OTC architecture allows a large-scale dot-product array and can be integrated into a photonic chip. The feasibility of the OTC and its effectiveness on neural network training are verified with numerical simulations.展开更多
We experimentally study optical homodyne and heterodyne detections with the same setup, which is flexible to manipulate the signal sideband modulation. When the modulation only generates a single signal sideband, the ...We experimentally study optical homodyne and heterodyne detections with the same setup, which is flexible to manipulate the signal sideband modulation. When the modulation only generates a single signal sideband, the light field measurement by mixing the single sideband at ω0 ±? with a strong local oscillator at the carrier frequency ω0on a beam splitter becomes balanced heterodyne detection. When two signal sidebands at ω0 ±? are generated and the relative phase of the two sidebands is locked, this measurement corresponds to optical balanced homodyne detection. With this setup, we may confirm directly that the signal-to-noise ratio with heterodyne detection is two-fold worse than that with homodyne detection. This work will have important applications in quantum state measurement and quantum information.展开更多
Performing homodyne detection at a single output port of a squeezed-state light interferometer and then separating the measurement quadrature into two intervals can realize super-resolving and super-sensitive phase me...Performing homodyne detection at a single output port of a squeezed-state light interferometer and then separating the measurement quadrature into two intervals can realize super-resolving and super-sensitive phase measurements,which is equivalent to a binary-outcome measurement.Obviously,the single-port homodyne detection may lose almost part of the phase information,reducing the estimation precision.Here,we propose a data-processing technique over the doubleport homodyne detection,where the two-dimensional measurement quadrature(p1,p2)has been divided into two regions.With such a binary-outcome measurement,we estimate the phase shift accumulated in the interferometer by inverting the output signal.By analyzing the full width at half maximum of the signal and the phase sensitivity,we show that both the resolution and the achievable sensitivity are better than that of the previous binary-outcome scheme.展开更多
不同用户接入终端的出现使得光接入系统中上行链路的通信带宽需求急剧增加,低传输成本、高频带利用率的上行多进制光信号接入成为必然选择。设计了一种上行八进制相移键控信号并进行零差相干探测的新方案。该方案中,在光网络单元中级联...不同用户接入终端的出现使得光接入系统中上行链路的通信带宽需求急剧增加,低传输成本、高频带利用率的上行多进制光信号接入成为必然选择。设计了一种上行八进制相移键控信号并进行零差相干探测的新方案。该方案中,在光网络单元中级联3个相位电光调制器实现了高频带利用率八进制相移键控光信号的产生,在光线路终端中采用下行光信号载波作为混频源结合数字信号处理模块,实现了上行光信号的零差相干探测,相比较只采用相干探测技术的方案其接收机灵敏度值的提高超过了2 d B。展开更多
基金Supported by the National Fundamental Research Program under Grant No.2006CB921106National Natural Science Foundation of China under Grant Nos.10874098 and 10775076
文摘In this paper, we propose a deterministic quantum communication protocol using weak coherent states and pulsed homodyne detection. In this protocol, the communication parties exchange their secret information deterministicaJly in two rounds. The devices and efficiency of the protocol are discussed respectively. We also show the security of the protocol against intercept-resend and Trojan-Horse eavesdropping attacks.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.11654002,61575114,11874250,and 11804207)National Key Research and Development Program of China(No.2016YFA0301401)+2 种基金Program for Sanjin Scholar of Shanxi ProvinceProgram for Outstanding Innovative Teams of Higher Learning Institutions of ShanxiFund for Shanxi “1331 Project”Key Subjects Construction
文摘Squeezed states belong to the most prominent non-classical resources.They have compelling applications in precise measurement, quantum computation, and detection.Here, we report on the direct measurement of 13.8 d B squeezed vacuum states by improving the interference efficiency and gain of balanced homodyne detection.By employing an auxiliary laser beam, the homodyne visibility is increased to 99.8%.The equivalent loss of the electronic noise is reduced to 0.05% by integrating a junction field-effect transistor(JFET) buffering input and another JFET bootstrap structure in the balanced homodyne detector.
基金supported by the National Key R&D Program of China (No.2019YFB2203700)the National Natural Science Foundation of China (No.61822508)。
文摘We propose an optical tensor core(OTC) architecture for neural network training. The key computational components of the OTC are the arrayed optical dot-product units(DPUs). The homodyne-detection-based DPUs can conduct the essential computational work of neural network training, i.e., matrix-matrix multiplication. Dual-layer waveguide topology is adopted to feed data into these DPUs with ultra-low insertion loss and cross talk. Therefore, the OTC architecture allows a large-scale dot-product array and can be integrated into a photonic chip. The feasibility of the OTC and its effectiveness on neural network training are verified with numerical simulations.
基金supported by the National Basic Research Program of China(Grant No.2011CB921601)the National Natural Science Foundation of China(Grant Nos.10725416 and 60821004)
文摘We experimentally study optical homodyne and heterodyne detections with the same setup, which is flexible to manipulate the signal sideband modulation. When the modulation only generates a single signal sideband, the light field measurement by mixing the single sideband at ω0 ±? with a strong local oscillator at the carrier frequency ω0on a beam splitter becomes balanced heterodyne detection. When two signal sidebands at ω0 ±? are generated and the relative phase of the two sidebands is locked, this measurement corresponds to optical balanced homodyne detection. With this setup, we may confirm directly that the signal-to-noise ratio with heterodyne detection is two-fold worse than that with homodyne detection. This work will have important applications in quantum state measurement and quantum information.
基金the Science Foundation of Zhejiang Sci-Tech University,grant number 18062145-Ythe National Natural Science Foundation of China(NSFC)grant number12075209.
文摘Performing homodyne detection at a single output port of a squeezed-state light interferometer and then separating the measurement quadrature into two intervals can realize super-resolving and super-sensitive phase measurements,which is equivalent to a binary-outcome measurement.Obviously,the single-port homodyne detection may lose almost part of the phase information,reducing the estimation precision.Here,we propose a data-processing technique over the doubleport homodyne detection,where the two-dimensional measurement quadrature(p1,p2)has been divided into two regions.With such a binary-outcome measurement,we estimate the phase shift accumulated in the interferometer by inverting the output signal.By analyzing the full width at half maximum of the signal and the phase sensitivity,we show that both the resolution and the achievable sensitivity are better than that of the previous binary-outcome scheme.
文摘不同用户接入终端的出现使得光接入系统中上行链路的通信带宽需求急剧增加,低传输成本、高频带利用率的上行多进制光信号接入成为必然选择。设计了一种上行八进制相移键控信号并进行零差相干探测的新方案。该方案中,在光网络单元中级联3个相位电光调制器实现了高频带利用率八进制相移键控光信号的产生,在光线路终端中采用下行光信号载波作为混频源结合数字信号处理模块,实现了上行光信号的零差相干探测,相比较只采用相干探测技术的方案其接收机灵敏度值的提高超过了2 d B。
