Temperature-induced emergence of Wigner correlations in a STM-probed one-dimensional quantum dot

TL;DR

This paper demonstrates that increasing temperature suppresses Friedel oscillations but enhances Wigner correlations in a one-dimensional quantum dot, with implications for STM measurements and understanding electron interactions.

Contribution

It reveals how temperature selectively stabilizes Wigner correlations over Friedel oscillations in a strongly interacting quantum dot, using the spin coherent Luttinger liquid framework.

Findings

Wigner oscillations become more prominent at higher temperatures.

Friedel oscillations are suppressed by thermal fluctuations.

STM measurements can confirm the temperature-dependent correlation behavior.

Abstract

The temperature-induced emergence of Wigner correlations over finite-size effects in a strongly interacting one-dimensional quantum dot are studied in the framework of the spin coherent Luttinger liquid. We demonstrate that, for temperatures comparable with the zero mode spin excitations, Friedel oscillations are suppressed by the thermal fluctuations of higher spin modes. On the other hand, the Wigner oscillations, sensitive to the charge mode only, are stable and become more visible. This behavior is proved to be robust both in the thermal electron density and in the linear conductance in the presence of an STM tip. This latter probe is not directly proportional to the electron density and may confirm the above phenomena with complementary and additional information.