Offset sideband locking to iodine for laser cooling on the ¹S₀ → ³P₁ transition of ¹⁷¹Yb

We present absolute frequency measurements of a laser stabilized using an offset sideband locking technique on the P(49)24-1 rovibrational transition of ¹²⁷I₂ near 556 nm. The P(49)24-1 transition is offset by 4.8 GHz from the intercombination transition of ¹⁷¹Yb. A dual-tone electro-optical modulator is employed to bridge this frequency gap, enabling frequency stabilization of the 556 nm laser near the Yb transition, achieving a fractional frequency stability of 1.2 × 10^-11 at one second. We thoroughly characterize the frequency shifts associated with this locking scheme, with typical systematic effects fractional uncertainties of 9 × 10^-12.