Precise determination of the isotope shift of Sr-88-Sr-87 optical lattice clock by sharing perturbations

摘要

We report on the isotope shift between Sr-88 and Sr-87 on the S-1(0)-P-3(0) clock transitions. The interleaved operation of an optical lattice clock with two isotopes allows the canceling out of common perturbations, such as the quadratic Zeeman shift, the clock-light shift, and the blackbody radiation shift. The isotope shift is determined to be 62 188 134 004(10) Hz, where the major uncertainty is introduced by the collisional shift that is distinct for each isotope. Our result allows us to determine the frequency of Sr-88-Sr-87 optical lattice clocks with a fractional uncertainty of 2 x 10(-17). The scheme is generally applicable for measuring the isotope shift with significantly reduced uncertainty. (C) 2017 The Japan Society of Applied Physics.