Tunably-polarized driving light controls the phase diagram of 1D quasicrystals and 2D quantum Hall matter

TL;DR

This paper investigates how tunably-polarized light influences the phase diagram of 1D quasicrystals and 2D quantum Hall systems, revealing new phases and transitions driven by electromagnetic polarization.

Contribution

It introduces a generalized driving scheme using arbitrary polarization light, uncovering a tessellated phase diagram with duality-protected metal-insulator transitions and critical phases.

Findings

Polarization controls phase transitions in quasicrystals and quantum Hall systems.

Circular or elliptical polarization induces an extended critical phase.

Proposes experimental realization with ultracold atoms.

Abstract

The well-known mapping between 1D quasiperiodic systems and 2D integer quantum Hall matter can also be applied in the presence of driving. Here we explore the effect of time-varying electric fields on the transport properties and phase diagram of Harper-Hofstadter materials. We consider light of arbitrary polarization illuminating a 2D electron gas at high magnetic field; this system maps to a 1D quasicrystal subjected to simultaneous phasonic and dipolar driving. We show that this generalized driving generates a tessellated phase diagram featuring a nested duality-protected pattern of metal-insulator transitions. Circularly or elliptically polarized light can create an extended critical phase, opening up a new route to achieving wavefunction multifractality without fine-tuning to a critical point. We describe in detail a path to experimental realization of these phenomena using lattice-trapped ultracold atoms.