Quantum fluids of self-assembled chains of polar molecules

TL;DR

This paper investigates quantum fluids formed by self-assembled chains of polar molecules in layered traps, revealing that only the longest chains undergo Bose-Einstein condensation at reduced temperatures.

Contribution

It introduces the concept of quantum liquids of dipolar chains, analyzing their properties and the conditions for Bose-Einstein condensation in such systems.

Findings

Long chains undergo Bose-Einstein condensation.

Condensation temperature is significantly reduced for the longest chains.

System stability depends on dipolar interaction strength and orientation.

Abstract

We study polar molecules in a stack of strongly confined pancake traps. When dipolar moments point perpendicular to the planes of the traps and are sufficiently strong, the system is stable against collapse but attractive interaction between molecules in different layers leads to the formation of extended chains of molecules, analogously to the chaining phenomenon in classical rheological electro- and magnetofluids. We analyze properties of the resulting quantum liquid of dipolar chains and show that only the longest chains undergo Bose-Einstein condensation with a strongly reduced condensation temperature. We discuss several experimental methods for studying chains of dipolar molecules.