Quantum Metrology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan.
Department of Applied Physics, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
Phys Rev Lett. 2018 Dec 28;121(26):263202. doi: 10.1103/PhysRevLett.121.263202.
We experimentally investigate the lattice-induced light shift by the electric-quadrupole (E2) and magnetic-dipole (M1) polarizabilities and the hyperpolarizability in Sr optical lattice clocks. Precise control of the axial as well as the radial motion of atoms in a one-dimensional lattice allows observing the E2-M1 polarizability difference. Measured polarizabilities determine an operational lattice depth to be 72(2)E_{R}, where the total light shift cancels to the 10^{-19} level, over a lattice-intensity variation of about 30%. This operational trap depth and its allowable intensity range conveniently coincide with experimentally feasible operating conditions for Sr optical lattice clocks.
我们通过实验研究了晶格诱导的光频移，包括电四极（E2）和磁偶极（M1）极化率以及 Sr 光学晶格钟中的超高极化率。精确控制原子在一维晶格中的轴向和径向运动，使得 E2-M1 极化率差异能够被观察到。测量得到的极化率确定了操作晶格深度为 72(2)E_{R}，其中晶格强度变化约 30%时，总光频移可被抵消到 10^{-19}的水平。该操作阱深度及其允许的强度范围与 Sr 光学晶格钟的实际可行的实验操作条件相吻合。
