Clock-line photoassociation of strongly bound dimers in a magic-wavelength lattice

TL;DR

This paper demonstrates the optical creation and spectroscopy of deeply bound $^{171}$Yb molecules using the clock transition, revealing an orbital Feshbach resonance and long-lived pair states, with implications for molecular clocks and multiorbital Fermi gases.

Contribution

It presents the first direct optical production of strongly bound Yb molecules and characterizes an orbital Feshbach resonance near 1300 G, advancing control of multiorbital interactions.

Findings

Observation of a magnetic-field-dependent orbital Feshbach resonance.

Demonstration of trap-insensitive free-to-bound transitions.

Measurement of intra- and interorbital scattering lengths and long pair lifetimes.

Abstract

We report on the direct optical production and spectroscopy of $^1\mathrm{S}_0\mbox{-}^3\mathrm{P}_0$ molecules with large binding energy using the clock transition of $^{171}\mathrm{Yb}$, and on the observation of the associated orbital Feshbach resonance near $1300\,\mathrm{G}$. We measure the magnetic field dependence of the closed-channel dimer and of the open-channel pair state energy via clock-line spectroscopy in a deep optical lattice. In addition, we show that the free-to-bound transition into the dimer can be made first-order insensitive to the trap depth by choice of the lattice wavelength. Finally, we determine the fundamental intra- and interorbital scattering lengths and probe the stability of the corresponding pair states, finding long lifetimes in both interorbital interaction channels. These results are promising both for molecular clocks and for the preparation of strongly-interacting multiorbital Fermi gases.