Spatially varying interactions induced in atomic gases by optical Feshbach resonance

TL;DR

This paper explores how optical Feshbach resonance can create spatially varying interactions in ultra-cold atomic gases, enabling the study of novel phenomena like superfluid enclaves and normal-gas cores, with potential applications in atomtronics and superconductivity analogs.

Contribution

It proposes methods to induce and observe spatially varying interactions in ultra-cold gases, revealing new structures and phenomena not seen in traditional setups.

Findings

Feasible experimental setups for creating spatially varying interactions.

Potential to observe superfluid enclaves within Mott insulators.

Analogies to superconducting islands in high-temperature superconductors.

Abstract

Optical Feshbach resonance is capable of inducing spatially varying interactions in ultra-cold atoms. Its applications to pancake-shaped clouds of bosons and fermions enable one to study several fresh phenomena. We examine possibilities of inducing counter-intuitive structures such as creating a superfluid enclave inside a Mott insulator for bosons and a normal-gas core enclosed by a superfluid shell for fermions. We discuss feasible experimental setups and signatures of those interesting structures, which can be very different from common structures observed in experiments so far. While a superfluid enclave in a Mott insulator can be useful for constructing atomic devices for atomtronics, superconducting islands observed in scanning-tunneling microscopy of heavily underdoped high-temperature superconductors may be studied with cold Fermi gases with spatially varying attractions.