Optically levitated oscillators in high vacuum have excellent environmental isolation and low mass compared with conventional solid-state sensors,which makes them suitable for ultrasensitive force detection.The force ...Optically levitated oscillators in high vacuum have excellent environmental isolation and low mass compared with conventional solid-state sensors,which makes them suitable for ultrasensitive force detection.The force resolution usually scales with the measurement bandwidth,which represents the ultimate detection capability of the system under ideal conditions if sufficient time is provided for measurement.However,considering the stability of a real system,a method based on the Allan variance is more reliable to evaluate the actual force detection performance.In this study,a levitated optomechanical system with a force detection sensitivity of 6.33±1.62 zN/Hz^(1/2)was demonstrated.And for the first time,the Allan variance was introduced to evaluate the system stability due to the force sensitivity fluctuations.The force detection resolution of 166.40±55.48 yN was reached at the optimal measurement time of 2751 s.The system demonstrated in this work has the best force detection performance in both sensitivity and resolution that have been reported so far for optically levitated particles.The reported high-sensitivity force detection system is an excellent candidate for the exploration of new physics such as fifth force searching,high-frequency gravitational waves detection,dark matter research and so on.展开更多
为了实现采煤机在作业中摇臂与连接架之间的连接销轴的受力实时检测,提出了一种基于压电振动俘能自供电销轴受力检测系统,不仅为销轴过载保护提供了重要依据,而且有效解决了经常更换电源的问题。将采煤机工作过程中的振动能量有效的转...为了实现采煤机在作业中摇臂与连接架之间的连接销轴的受力实时检测,提出了一种基于压电振动俘能自供电销轴受力检测系统,不仅为销轴过载保护提供了重要依据,而且有效解决了经常更换电源的问题。将采煤机工作过程中的振动能量有效的转换为电能,为传感器和无线采集模块提供稳定充足的电能。通过多个现场测试表明,检测系统的自供电性能稳定,截取采煤机900s内工作时间进行分析,得到销轴X、Y、Z方向上最大载荷分别为16.261 73 k N、51.321 43 k N、303.939 31 k N,测试结果与实际工况相接近,验证了基于压电振动俘能装置的自供电销轴受力检测系统应用于实际工程检测的可行性和精确性。展开更多
Ultra-broadband,intense,coherent terahertz(THz)radiation can be generated,detected,and manipulated using laser-induced gas or liquid plasma as both the THz wave transmitter and detector,with a frequency coverage spann...Ultra-broadband,intense,coherent terahertz(THz)radiation can be generated,detected,and manipulated using laser-induced gas or liquid plasma as both the THz wave transmitter and detector,with a frequency coverage spanning across and beyond the whole THz gap."Such a research topic is termed plasma-based THz wave photonics in gas and liquid phases."In this paper,we review the most important experimental and theoretical works of the topic in the non-relativistic region with pump laser intensity below 1018 W/cm^(2).展开更多
基金supported by grants from the National Natural Science Foundation of China(62005248,62075193)Major Project of Natural Science Foundation of Zhejiang Province(LD22F050002)+2 种基金Major Scientific Research Project of Zhejiang Lab(2019MB0AD01,2021MB0AL02,2022MB0AL02)the Fundamental Research Funds for the Central Universities,China(2016XZZX00401 and 2018FZA5002)the National Program for Special Support of Top-Notch Young Professionals(W02070390),China.
文摘Optically levitated oscillators in high vacuum have excellent environmental isolation and low mass compared with conventional solid-state sensors,which makes them suitable for ultrasensitive force detection.The force resolution usually scales with the measurement bandwidth,which represents the ultimate detection capability of the system under ideal conditions if sufficient time is provided for measurement.However,considering the stability of a real system,a method based on the Allan variance is more reliable to evaluate the actual force detection performance.In this study,a levitated optomechanical system with a force detection sensitivity of 6.33±1.62 zN/Hz^(1/2)was demonstrated.And for the first time,the Allan variance was introduced to evaluate the system stability due to the force sensitivity fluctuations.The force detection resolution of 166.40±55.48 yN was reached at the optimal measurement time of 2751 s.The system demonstrated in this work has the best force detection performance in both sensitivity and resolution that have been reported so far for optically levitated particles.The reported high-sensitivity force detection system is an excellent candidate for the exploration of new physics such as fifth force searching,high-frequency gravitational waves detection,dark matter research and so on.
文摘为了实现采煤机在作业中摇臂与连接架之间的连接销轴的受力实时检测,提出了一种基于压电振动俘能自供电销轴受力检测系统,不仅为销轴过载保护提供了重要依据,而且有效解决了经常更换电源的问题。将采煤机工作过程中的振动能量有效的转换为电能,为传感器和无线采集模块提供稳定充足的电能。通过多个现场测试表明,检测系统的自供电性能稳定,截取采煤机900s内工作时间进行分析,得到销轴X、Y、Z方向上最大载荷分别为16.261 73 k N、51.321 43 k N、303.939 31 k N,测试结果与实际工况相接近,验证了基于压电振动俘能装置的自供电销轴受力检测系统应用于实际工程检测的可行性和精确性。
基金supported by the National Natural Science Foundation of China(Nos.62075157,61875151,and 62235013)Tianjin Municipal Fund for Distinguished Young Scholars(No.20JCJQJC00190)+3 种基金Key Fund of Shenzhen Natural Science Foundation(No.JCYJ20200109150212515)National Key Research and Development Program of China(No.2017YFA0701000)Prof.Xi-Cheng Zhang in The Institute of Optics at University of Rochester has support from the Air Force Office of Scientific Research(Nos.FA9550-21-1-0389 and FA9550-21-1-0300)the National Science Foundation(No.ECCS-2152081).
文摘Ultra-broadband,intense,coherent terahertz(THz)radiation can be generated,detected,and manipulated using laser-induced gas or liquid plasma as both the THz wave transmitter and detector,with a frequency coverage spanning across and beyond the whole THz gap."Such a research topic is termed plasma-based THz wave photonics in gas and liquid phases."In this paper,we review the most important experimental and theoretical works of the topic in the non-relativistic region with pump laser intensity below 1018 W/cm^(2).
