Crystalline Phases of Laser-Driven Dipolar Bose-Einstein Condensates

TL;DR

This paper investigates the crystallization phenomena in laser-driven dipolar Bose-Einstein condensates, revealing complex density patterns and proposing feasible methods for experimental realization of these crystalline states.

Contribution

It introduces the emergence of complex and aperiodic crystalline phases due to competing long-range interactions in dipolar BECs, with dynamic state-preparation schemes.

Findings

Multiple roton minima lead to different crystalline length scales

Simultaneous roton softening results in complex density patterns

Feasible experimental schemes for crystalline state preparation

Abstract

Although crystallization is a ubiquitous phenomenon in nature, crystal formation and melting still remain fascinating processes with several open questions yet to be addressed. In this work, we study the emergent crystallization of a laser-driven dipolar Bose-Einstein condensate due to the interplay between long-range magnetic and effectively infinite-range light-induced interactions. The competition between these two interactions results in a collective excitation spectrum with two roton minima that introduce two different length scales at which crystalline order can emerge. In addition to the formation of regular crystals with simple periodic patterns due to the softening of one of the rotons, we find that both rotons can also soften simultaneously, resulting in the formation of exotic, complex periodic or aperiodic density patterns. We also demonstrate dynamic state-preparation schemes for achieving all the found crystalline ground states for experimentally relevant and feasible parameter regimes