1.

Record Nr.

UNINA9910349510103321

Autore

Schreiber Katherine A

Titolo

Ground States of the Two-Dimensional Electron System at Half-Filling under Hydrostatic Pressure [[electronic resource] /] / by Katherine A. Schreiber

Pubbl/distr/stampa

Cham : , : Springer International Publishing : , : Imprint : Springer, , 2019

ISBN

3-030-26322-3

Edizione

[1st ed. 2019.]

Descrizione fisica

1 online resource (XIII, 101 p. 50 illus., 39 illus. in color.)

Collana

Springer Theses, Recognizing Outstanding Ph.D. Research, , 2190-5053

Disciplina

530.474

Soggetti

Phase transitions (Statistical physics)

Optical materials

Electronic materials

Low temperature physics

Low temperatures

Solid state physics

Phase Transitions and Multiphase Systems

Optical and Electronic Materials

Low Temperature Physics

Solid State Physics

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Nota di contenuto

Chapter 1 Introduction -- Chapter 2 The Quantum Hall Nematic Phase -- Chapter 3 Low Temperature Measurement Techniques -- Chapter 4 The Quantum Hall Effect and Hydrostatic Pressure -- Chapter 5 The Fractional Quantum Hall State-to-Nematic Phase Transition Under Hydrostatic Pressure -- Chapter 6 Universality of the Fractional Quantum Hall State-to-Nematic Phase Transition at Half-Filling in the Second Landau Level -- Chapter 7 Origin of the Fractional Quantum Hall State-to-Nematic Phase Transition in the Second Landau Level -- References.

Sommario/riassunto

This thesis presents the discovery of a surprising phase transition between a topological and a broken symmetry phase. Phase transitions



between broken symmetry phases involve a change in symmetry and those between topological phases require a change in topological order; in rare cases, however, transitions may occur between these two broad classes of phases in which the vanishing of the topological order is accompanied by the emergence of a broken symmetry. This thesis describes observations of such a special phase transition in the two-dimensional electron gas confined in the GaAs/AlGaAs structures. When tuned by hydrostatic pressure, the ν = 5/2 and ν = 7/2 fractional quantum Hall states, believed to be prototypical non-Abelian topological phases of the Pfaffian universality class, give way to an electronic nematic phase. Remarkably, the fractional quantum Hall states involved are due to pairing of emergent particles called composite fermions. The findings reported here, therefore, provide an interesting example of competition of pairing and nematicity. This thesis provides an introduction to quantum Hall physics of the two-dimensional electron gas, contains details of the high pressure experiments, and offers a discussion of the ramifications and of the origins of the newly reported phase transition.