Spatially varying interactions induced in ultra-cold atoms by optical Feshbach resonance

Optical Feshbach resonance can induce 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 unexplored structures such as a bosonic superfluid enclave inside a Mott insulator and a normal-gas core enclosed by a fermionic superfluid shell. We discuss feasible experimental setups and signatures of those interesting structures. While a superfluid enclave in a Mott insulator may be useful for atomic devices in atomtronics, the superconducting islands observed in scanning-tunneling microscopy of heavily underdoped high-temperature superconductors may be simulated by ultra-cold fermions.