Trapping induced frequency shifts by comparison of two Sr optical lattice clocks at the 10−17 level

We present a comprehensive study of the frequency shifts associated with the lattice potential in Sr lattice clocks. By comparing two such clocks with a frequency stability better than 5.10
^-17
after one hour of averaging time, and varying the lattice depth up to U
₀
= 900 E
_r
with E
_r
being the recoil energy, we evaluate lattice related shifts with an unprecedented accuracy.