p-Wave Optical Feshbach Resonances in Yb-171

TL;DR

This paper explores using optical Feshbach resonances to control p-wave interactions in ultracold Yb-171 fermions, aiming to suppress three-body losses and enable novel superfluid phases in optical lattices.

Contribution

It introduces a method to tune p-wave interactions via optical Feshbach resonances near long-range molecular states, reducing losses compared to magnetic Feshbach resonances.

Findings

Calculated molecular bound-state spectrum including magnetic field effects.

Demonstrated controllability of elastic and inelastic scattering rates.

Proposed conditions for realizing three-color superfluidity in optical lattices.

Abstract

We study the use of an optical Feshbach resonance to modify the p-wave interaction between ultracold polarized Yb-171 spin-1/2 fermions. A laser exciting two colliding atoms to the 1S_0 + 3P_1 channel can be detuned near a purely-long-range excited molecular bound state. Such an exotic molecule has an inner turning point far from the chemical binding region and thus three-body-recombination in the Feshbach resonance will be highly suppressed in contrast to that typically seen in a ground state p-wave magnetic Feshbach resonance. We calculate the excited molecular bound-state spectrum using a multichannel integration of the Schr\"{o}dinger equation, including an external perturbation by a magnetic field. From the multichannel wave functions, we calculate the Feshbach resonance properties, including the modification of the elastic p-wave scattering volume and inelastic spontaneous scattering rate. The use of magnetic fields and selection rules for polarized light yields a highly controllable system. We apply this control to propose a toy model for three-color superfluidity in an optical lattice for spin-polarized Yb-171, where the three colors correspond to the three spatial orbitals of the first excited p-band. We calculate the conditions under which tunneling and on-site interactions are comparable, at which point quantum critical behavior is possible.