Excitonic coherent states: symmetries and thermalization

TL;DR

This paper introduces a new coherent state construction for excitonic systems based on a Keldysh conjecture, revealing novel symmetries and analyzing thermal properties relevant to exciton behavior and Bose-Einstein condensation in semiconductors.

Contribution

It presents a new bounded coherent state framework for excitons, uncovering symmetry transformations and thermalization properties within a quantum field theoretical approach.

Findings

Identified new symmetry transformations related to excitonic states.

Analyzed thermal properties using the group structure of the model.

Provided insights into exciton behavior at finite temperatures.

Abstract

In previous work [1] new bounded coherent states construction, based on a Keldysh conjecture, was introduced. As was shown in [1] the particular group structure arising from the model leads to new symmetry transformations for the coherent states system. As was shown, the emergent new symmetry transformation is reminiscent of the Bogoliubov ones and was successfully applied to describe an excitonic system showing that is intrinsically related to the stability and its general physical behavior. The group theoretical structure of the model permits to analyze its thermal properties in theoretical frameworks that arise as a consequence of the definition of the squeezed-coherent states as transformed vacua under the automorphism group of the commutation relations, as the thermofield dynamics case given by Umezawa and other similar developments [5]. On the other hand, the idea of a possible Bose--Einstein condensation (BEC) of excitons in semiconductors has attracted the attention of both experimentalists and theoreticians for more than three decades being one of the main questions what happens with the influence of non zero temperature in the case that such condensation really exists [2]. In this paper we considered the theoretical treatment of the excitonic behaviour by mean a new coherent state construction of bounded states in a quantum field theoretical context.