Realizing time crystals in discrete quantum few-body systems

TL;DR

This paper demonstrates how time crystals, a phase of matter exhibiting time translation symmetry breaking, can be realized in small quantum systems like cold atoms and superconducting qubits, using effective spin chain models.

Contribution

It introduces a method to realize and analyze time crystals in few-body quantum systems, bridging cold atom experiments and superconducting circuits.

Findings

Time crystals can be observed in small, controlled quantum systems.

Effective spin chain models can describe the dynamics of these systems.

Proposed experimental parameters for superconducting circuits.

Abstract

The exotic phenomenon of time translation symmetry breaking under periodic driving - the time crystal - has been shown to occur in many-body systems even in clean setups where disorder is absent. In this work, we propose the realization of time-crystals in few-body systems, both in the context of trapped cold atoms with strong interactions and of a circuit of superconducting qubits. We show how these two models can be treated in a fairly similar way by adopting an effective spin chain description, to which we apply a simple driving protocol. We focus on the response of the magnetization in the presence of imperfect pulses and interactions, and show how the results can be interpreted, in the cold atomic case, in the context of experiments with trapped bosons and fermions. Furthermore, we provide a set of realistic parameters for the implementation of the superconducting circuit.