Atomic quantum gases in Kagom\'e lattices

TL;DR

This paper explores the creation and control of trimerized Kagomé optical lattices and investigates the rich low-temperature quantum phases of atomic gases, including Mott insulators, quantum magnets, and spin liquids.

Contribution

It introduces a method to generate trimerized Kagomé lattices and studies their quantum many-body physics, revealing novel phases like fractional Mott states and quantum spin liquids.

Findings

Bose gas exhibits a Mott transition at fractional filling.

Fermi gas at 2/3 filling acts as a quantum magnet.

Fermi-Fermi mixtures show spin liquid behavior with resonating valence bonds.

Abstract

We demonstrate the possibility of creating and controlling an ideal and \textit{trimerized} optical Kagom\'e lattice, and study the low temperature physics of various atomic gases in such lattices. In the trimerized Kagom\'e lattice, a Bose gas exhibits a Mott transition with fractional filling factors, whereas a spinless interacting Fermi gas at 2/3 filling behaves as a quantum magnet on a triangular lattice. Finally, a Fermi-Fermi mixture at half filling for both components represents a frustrated quantum antiferromagnet with a resonating-valence-bond ground state and quantum spin liquid behavior dominated by continuous spectrum of singlet and triplet excitations. We discuss the method of preparing and observing such quantum spin liquid employing molecular Bose condensates.