A nuclear spin gyroscope based on an alkali-metal–noble-gas co-magnetometer operated in spin-exchange relaxationfree(SERF) regime is a promising atomic rotation sensor for its ultra-high fundamental sensitivity. Howe...A nuclear spin gyroscope based on an alkali-metal–noble-gas co-magnetometer operated in spin-exchange relaxationfree(SERF) regime is a promising atomic rotation sensor for its ultra-high fundamental sensitivity. However, the fluctuation of probe light intensity is one of the main technical error sources that limits the bias stability of the gyroscope. Here we propose a novel method to suppress the bias error induced by probe light intensity fluctuations. This method is based on the inherent magnetic field response characteristics of the gyroscope. By the application of a bias magnetic field, the gyroscope can be tuned to a working point where the output signal is insensitive to probe light intensity variation, referred to herein as ‘zero point’, thus the bias error induced by intensity fluctuations can be completely suppressed. The superiority of the method was verified on a K–Rb–21 Ne co-magnetometer, and a bias stability of approximately 0.01°/h was obtained. In addition, the method proposed here can remove the requirement of the closed-loop control of probe light intensity, thereby facilitating miniaturization of the gyroscope volume and improvement of reliability.展开更多
Bubble plumes are important during the process of air-sea exchange,and optical-fiber phase detection is a suitable way to observe bubble plumes entrained by breaking waves.This paper designs a new optical-fiber probe(...Bubble plumes are important during the process of air-sea exchange,and optical-fiber phase detection is a suitable way to observe bubble plumes entrained by breaking waves.This paper designs a new optical-fiber probe(OFP)made of sapphire to overcome the limitations of existing materials(e.g.,high brittleness,poor corrosion resistance,and narrow bandwidth)and thereby enhance the detection performance of the OFP by improving its structure.Based on total internal reflection and light refraction,a simulation model of the probe is established in the Zemax optical design software to optimize the probe tip and matching mode of the two probe tips.The results show that the optimum OFP tip is a conical sapphire one with a cone angle of 35°.Tests are then conducted on a bespoke OFP sensor,the results of which are consistent with those predicted theoretically.The simulation results lay the foundation for the integrated design of OFP sensors and the optimization of their internal optics.The findings could also be applied to OFPs with multiple tips.展开更多
Propagation of a signal beam in an Al Ga As/Ga As waveguide multiple-prism light deflector is theoretically investigated by solving the scalar Helmholtz equation to obtain the dependences of the temporal and spatial r...Propagation of a signal beam in an Al Ga As/Ga As waveguide multiple-prism light deflector is theoretically investigated by solving the scalar Helmholtz equation to obtain the dependences of the temporal and spatial resolvable characteristics of the ultrafast deflector on the material dispersion of Ga As including group velocity dispersion and angular dispersion,interface reflection,and interface scattering of multiple-prism deflector.Furthermore,we experimentally confirm that,in this ultrafast beam deflection device,the deflecting angle of the signal light beam is linear with the pump fluence and the temporal resolution of the ultrafast deflection is 10 ps.Our results show that the improvement of the temporal and spatial resolvable performances is possible by properly choosing the structural parameters and enhancing the quality of the device.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2016YFB0501600 and 2017YFB0503100)the National Natural Science Foundation of China(Grant Nos.61773043,61673041,and 61721091)
文摘A nuclear spin gyroscope based on an alkali-metal–noble-gas co-magnetometer operated in spin-exchange relaxationfree(SERF) regime is a promising atomic rotation sensor for its ultra-high fundamental sensitivity. However, the fluctuation of probe light intensity is one of the main technical error sources that limits the bias stability of the gyroscope. Here we propose a novel method to suppress the bias error induced by probe light intensity fluctuations. This method is based on the inherent magnetic field response characteristics of the gyroscope. By the application of a bias magnetic field, the gyroscope can be tuned to a working point where the output signal is insensitive to probe light intensity variation, referred to herein as ‘zero point’, thus the bias error induced by intensity fluctuations can be completely suppressed. The superiority of the method was verified on a K–Rb–21 Ne co-magnetometer, and a bias stability of approximately 0.01°/h was obtained. In addition, the method proposed here can remove the requirement of the closed-loop control of probe light intensity, thereby facilitating miniaturization of the gyroscope volume and improvement of reliability.
文摘Bubble plumes are important during the process of air-sea exchange,and optical-fiber phase detection is a suitable way to observe bubble plumes entrained by breaking waves.This paper designs a new optical-fiber probe(OFP)made of sapphire to overcome the limitations of existing materials(e.g.,high brittleness,poor corrosion resistance,and narrow bandwidth)and thereby enhance the detection performance of the OFP by improving its structure.Based on total internal reflection and light refraction,a simulation model of the probe is established in the Zemax optical design software to optimize the probe tip and matching mode of the two probe tips.The results show that the optimum OFP tip is a conical sapphire one with a cone angle of 35°.Tests are then conducted on a bespoke OFP sensor,the results of which are consistent with those predicted theoretically.The simulation results lay the foundation for the integrated design of OFP sensors and the optimization of their internal optics.The findings could also be applied to OFPs with multiple tips.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11274377 and 61176006)the State Major Research Equipment ProChina(Grant No.ZDY2011-2)
文摘Propagation of a signal beam in an Al Ga As/Ga As waveguide multiple-prism light deflector is theoretically investigated by solving the scalar Helmholtz equation to obtain the dependences of the temporal and spatial resolvable characteristics of the ultrafast deflector on the material dispersion of Ga As including group velocity dispersion and angular dispersion,interface reflection,and interface scattering of multiple-prism deflector.Furthermore,we experimentally confirm that,in this ultrafast beam deflection device,the deflecting angle of the signal light beam is linear with the pump fluence and the temporal resolution of the ultrafast deflection is 10 ps.Our results show that the improvement of the temporal and spatial resolvable performances is possible by properly choosing the structural parameters and enhancing the quality of the device.