The Ramsey fringes with a linewidth of 45 Hz and a signal-to-noise ratio of 120 are demonstrated for a integrating sphere atom clock.The cycle time of the atom clock is reduced to 80 ms with the help of a pulsed cooli...The Ramsey fringes with a linewidth of 45 Hz and a signal-to-noise ratio of 120 are demonstrated for a integrating sphere atom clock.The cycle time of the atom clock is reduced to 80 ms with the help of a pulsed cooling method.This result indicates that the short-term stability of the clock is in the order of 10^(-12).展开更多
This study presents an experiment on diffuse light cooling of atoms in a cylindrical cavity.We focus on the controlling of the shape of the atom cloud by placing the cooling beams in appropriate positions.The Gauss-li...This study presents an experiment on diffuse light cooling of atoms in a cylindrical cavity.We focus on the controlling of the shape of the atom cloud by placing the cooling beams in appropriate positions.The Gauss-like shape of the atomic cloud is demonstrated.The number of cold atoms detected in the cavity is increased,thereby improving the signal-to-noise ratio of the clock signal.展开更多
We present an experiment on the measurement of the spatial distribution of cold atoms in a ceramic cell.The atoms are first cooled by diffusing light produced by multiple scattering of laser light at the inner surface...We present an experiment on the measurement of the spatial distribution of cold atoms in a ceramic cell.The atoms are first cooled by diffusing light produced by multiple scattering of laser light at the inner surface of the cell.An inhomogeneous magnetic field is applied after the atoms are cooled by using a pair of anti-Helmholtz coils,and thus the shift of atomic magnetic sub-levels is position-dependent.We move the anti-Helmholtz coils point by point while keeping the probe laser beam resonant with the cold atoms at zero magnetic field.The number of cold atoms at different positions can be extracted by detecting the absorption to the probe beam.The density of the cold atoms in the cell is measured in two dimensions perpendicular and parallel to the tube connecting to the vacuum system,respectively.The results show that at the center of the cell,fewer atoms exist due to the leakage of diffuse light into the hole connecting to the vacuum pump.The method we developed is used to detect cold atoms in a region where imaging is impossible.展开更多
We investigate an effective grooved 2D ion chip design and optimize the ratio between the size of the rf electrodes and the groove.We calculate the optimal size of the groove using the analytical model,which was intro...We investigate an effective grooved 2D ion chip design and optimize the ratio between the size of the rf electrodes and the groove.We calculate the optimal size of the groove using the analytical model,which was introduced by House,and the optimum result is obtained.We also obtain the simulated scattering points with the finite element analysis method.The analytical curve and simulated scattering points are coincident with each other.It is shown that this analytical model also fits for the grooved planar ion chip.Thus the optimum grooved 2D planar ion chip design could be obtained.It is effective for scalable quantum information processing.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11074262 and 11034008,and the National High-Tech Research and Development Program of China under Grant No 2012AA120702.
文摘The Ramsey fringes with a linewidth of 45 Hz and a signal-to-noise ratio of 120 are demonstrated for a integrating sphere atom clock.The cycle time of the atom clock is reduced to 80 ms with the help of a pulsed cooling method.This result indicates that the short-term stability of the clock is in the order of 10^(-12).
基金Supported by the National Natural Science Foundation of China under Grant Nos 11074262 and 11034008the National High-Tech Research and Development Program under Grant No 2012AA120702.
文摘This study presents an experiment on diffuse light cooling of atoms in a cylindrical cavity.We focus on the controlling of the shape of the atom cloud by placing the cooling beams in appropriate positions.The Gauss-like shape of the atomic cloud is demonstrated.The number of cold atoms detected in the cavity is increased,thereby improving the signal-to-noise ratio of the clock signal.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11074262,10874193 and 11034008.
文摘We present an experiment on the measurement of the spatial distribution of cold atoms in a ceramic cell.The atoms are first cooled by diffusing light produced by multiple scattering of laser light at the inner surface of the cell.An inhomogeneous magnetic field is applied after the atoms are cooled by using a pair of anti-Helmholtz coils,and thus the shift of atomic magnetic sub-levels is position-dependent.We move the anti-Helmholtz coils point by point while keeping the probe laser beam resonant with the cold atoms at zero magnetic field.The number of cold atoms at different positions can be extracted by detecting the absorption to the probe beam.The density of the cold atoms in the cell is measured in two dimensions perpendicular and parallel to the tube connecting to the vacuum system,respectively.The results show that at the center of the cell,fewer atoms exist due to the leakage of diffuse light into the hole connecting to the vacuum pump.The method we developed is used to detect cold atoms in a region where imaging is impossible.
基金by the National Natural Science Foundation of China under Grant No 1097421the Science and Technology Commission of the Shanghai Municipality Program under Grant No 08JC1420100.
文摘We investigate an effective grooved 2D ion chip design and optimize the ratio between the size of the rf electrodes and the groove.We calculate the optimal size of the groove using the analytical model,which was introduced by House,and the optimum result is obtained.We also obtain the simulated scattering points with the finite element analysis method.The analytical curve and simulated scattering points are coincident with each other.It is shown that this analytical model also fits for the grooved planar ion chip.Thus the optimum grooved 2D planar ion chip design could be obtained.It is effective for scalable quantum information processing.
