Based on single Cesium atoims trapped in a 1064 nm microscopic optical trap we have exhibited a single qubit encoded in the Cesium "clock states". The single qubit initialization, detection and the fast state rotati...Based on single Cesium atoims trapped in a 1064 nm microscopic optical trap we have exhibited a single qubit encoded in the Cesium "clock states". The single qubit initialization, detection and the fast state rotation with high efficiencies are demonstrated and this state manipulation is crucial for quantmn information processing. The ground ~ates Rabi flopping rate of 229.0 ± 0.6 kHz is realized hy a two-photon Raman process. A clock states dephasing time of 3.0 ± 0.7 ms is measured, while all irreversible homogeneous dephasing time of 124 ± 17 ms is achieved by using the spin-echo technique. This well-controlled single atom provides an ideal quantmn qubit and quantmn node for quantum information processing.展开更多
过去几十年中激光雷达的发展对于海洋监测有着重大意义,而星载单光子激光雷达以更高的分辨率和测量精度展现了其在海洋遥感中的优势地位。结合单光子探测器的响应特性,依据海面反射模型,提出了一个定量计算海面回波信号强度的理论模型...过去几十年中激光雷达的发展对于海洋监测有着重大意义,而星载单光子激光雷达以更高的分辨率和测量精度展现了其在海洋遥感中的优势地位。结合单光子探测器的响应特性,依据海面反射模型,提出了一个定量计算海面回波信号强度的理论模型。使用ICESat-2(The Ice, Cloud, and land Elevation Satellite 2)对地观测激光测高卫星搭载的先进地形激光测高系统(ATLAS)的参数作为输入,采用ICESat-2获取的ATL03数据统计回波信号强度和全球风场数据验证模型,模型在菲律宾海域统计的多轨数据较好,在海面风速为4~10 m/s的情况下,其均值误差为0.0037个光子/脉冲,均方根误差为0.153个光子/脉冲。分析得出了星载单光子海洋测高仪回波强度和海平面上方平均风速的关系,该结论对海平面上方风速反演提供了重要的理论依据。展开更多
胆胰管系统疾病的诊断以往主要依靠 B 超、CT 和内窥镜逆行胰胆管造影(ERCP)等检查.磁共振胆胰管成象(magneticresonance cholangiopancreatography,MRCP)是一种无创性显示胆胰管结构的新技术,自1991年德国学者 Wallner et al 首次报道...胆胰管系统疾病的诊断以往主要依靠 B 超、CT 和内窥镜逆行胰胆管造影(ERCP)等检查.磁共振胆胰管成象(magneticresonance cholangiopancreatography,MRCP)是一种无创性显示胆胰管结构的新技术,自1991年德国学者 Wallner et al 首次报道以来,已逐渐应用到临床,其前景十分广阔.目前国内外报道 MRCP 成象序列主要是快速自旋回波序列(fast展开更多
基金Acknowledgements This work was supported by the National Basic Research Program of China (Grant No. 2012CB921601) and the National Natural Science Foundation of China (Grants Nos. 11125418, 91336107, 61275210, 61227902, and 61121064).
文摘Based on single Cesium atoims trapped in a 1064 nm microscopic optical trap we have exhibited a single qubit encoded in the Cesium "clock states". The single qubit initialization, detection and the fast state rotation with high efficiencies are demonstrated and this state manipulation is crucial for quantmn information processing. The ground ~ates Rabi flopping rate of 229.0 ± 0.6 kHz is realized hy a two-photon Raman process. A clock states dephasing time of 3.0 ± 0.7 ms is measured, while all irreversible homogeneous dephasing time of 124 ± 17 ms is achieved by using the spin-echo technique. This well-controlled single atom provides an ideal quantmn qubit and quantmn node for quantum information processing.
文摘过去几十年中激光雷达的发展对于海洋监测有着重大意义,而星载单光子激光雷达以更高的分辨率和测量精度展现了其在海洋遥感中的优势地位。结合单光子探测器的响应特性,依据海面反射模型,提出了一个定量计算海面回波信号强度的理论模型。使用ICESat-2(The Ice, Cloud, and land Elevation Satellite 2)对地观测激光测高卫星搭载的先进地形激光测高系统(ATLAS)的参数作为输入,采用ICESat-2获取的ATL03数据统计回波信号强度和全球风场数据验证模型,模型在菲律宾海域统计的多轨数据较好,在海面风速为4~10 m/s的情况下,其均值误差为0.0037个光子/脉冲,均方根误差为0.153个光子/脉冲。分析得出了星载单光子海洋测高仪回波强度和海平面上方平均风速的关系,该结论对海平面上方风速反演提供了重要的理论依据。
文摘胆胰管系统疾病的诊断以往主要依靠 B 超、CT 和内窥镜逆行胰胆管造影(ERCP)等检查.磁共振胆胰管成象(magneticresonance cholangiopancreatography,MRCP)是一种无创性显示胆胰管结构的新技术,自1991年德国学者 Wallner et al 首次报道以来,已逐渐应用到临床,其前景十分广阔.目前国内外报道 MRCP 成象序列主要是快速自旋回波序列(fast