Optical control over bulk excitations in fractional quantum Hall systems

TL;DR

This paper explores optical methods to control and manipulate fractional excitations in quantum Hall systems, enabling potential experimental observation and quantum computation applications of these exotic quasiparticles.

Contribution

It introduces novel optical strategies, including angular momentum transfer and optical trapping, for microscopic control of fractional quasiparticles in quantum Hall systems.

Findings

Optical angular momentum can generate quasiholes and quasielectrons.

Optical potentials can trap and move quasiholes.

Controlled movement of quasiholes can imprint Berry phases.

Abstract

Local excitations in fractional quantum Hall systems are amongst the most intriguing objects in condensed matter, as they behave like particles of fractional charge and fractional statistics. In order to experimentally reveal these exotic properties and further to use such excitations for quantum computations, microscopic control over the excitations is necessary. Here we discuss different optical strategies to achieve such control. First, we propose that the application of a light field with non-zero orbital angular momentum can pump orbital angular momenta to electrons in a quantum Hall droplet. In analogy to Laughlin's argument, we show that this field can generate a quasihole or a quasielectron in such systems. Second, we consider an optical potential that can trap a quasihole, by repelling electrons from the region of the light beam. We simulate a moving optical field, which is able to control the position of the quasihole. This allows for imprinting the characteristic Berry phase which reflects the fractional charge of the quasihole.