Interaction effects in a microscopic quantum wire model with strong spin-orbit interaction

Autor(en)

G. W. Winkler, Martin Ganahl, Dirk Schuricht, H. G. Evertz, S. Andergassen

Abstrakt

Weinvestigate the effect of strong interactions on the spectral properties of quantum wires with strong Rashba spin-orbit (SO) interaction in a magnetic field, using a combination of matrix product state and bosonization techniques. Quantum wires with strong Rashba SO interaction and magnetic field exhibit a partial gap in one-half of the conducting modes. Such systems have attracted wide-spread experimental and theoretical attention due to their unusual physical properties, among which are spin-dependent transport, or a topological superconducting phase when under the proximity effect of an s-wave superconductor. As a microscopic model for the quantum wire we study an extended Hubbard model with SO interaction and Zeeman field. We obtain spin resolved spectral densities from the real-time evolution of excitations, and calculate the phase diagram. We find that interactions increase the pseudo gap at k = 0 and thus also enhance the Majorana-supporting phase and stabilize the helical spin order. Furthermore, we calculate the optical conductivity and compare it with the low energy spiral Luttinger liquid result, obtained from field theoretical calculations. With interactions, the optical conductivity is dominated by an excotic excitation of a bound soliton-antisoliton pair known as a breather state. Wevisualize the oscillating motion of the breather state, which could provide the route to their experimental detection in e.g. cold atom experiments.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

Eidgenössische Technische Hochschule Zürich, Technische Universität Graz, Perimeter Institute for Theoretical Physics, Utrecht University, University of California, Santa Barbara, Eberhard Karls Universität Tübingen

Journal

New Journal of Physics

Band

19

Anzahl der Seiten

16

ISSN

1367-2630

DOI

https://doi.org/10.1088/1367-2630/aa7027

Publikationsdatum

06-2017

Peer-reviewed

Ja

ÖFOS 2012

103036 Theoretische Physik, 103015 Kondensierte Materie

Schlagwörter

ASJC Scopus Sachgebiete

Allgemeine Physik und Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/45ae0907-99ff-4a7d-a017-bebbd3556607