Thermal radiation as a probe of one-dimensional electron liquids

TL;DR

This paper develops a theoretical framework for using thermal radiation to probe the non-Fermi liquid behavior and interactions in one-dimensional electron liquids, with potential experimental applications in systems like carbon nanotubes.

Contribution

It introduces a multipole expansion for radiation from Tomonaga-Luttinger liquids and shows how quadrupole radiation reveals key quantum liquid properties.

Findings

Quadrupole radiation encodes the Luttinger parameter.

Thermal radiation spectra reflect non-Fermi liquid behavior.

Proposed experimental detection in carbon nanotubes.

Abstract

Motivated by recent developments in the field of plasmonics, we develop the theory of radiation from one-dimensional electron liquids, showing that the spectrum of thermal radiation emitted from the system exhibits signatures of non-Fermi liquid behavior. We derive a multipole expansion for the radiation based on the Tomonaga-Luttinger liquid model. While the dipole radiation pattern is determined by the conductivity of the system, we demonstrate that the quadrupole radiation can reveal important features of the quantum liquid, such as the Luttinger parameter. Radiation offers a probe of the interactions of the system, including Mott physics as well as non-linear Luttinger liquid behavior. We show that these effects can be probed in current experiments on effectively one-dimensional electron liquids, such as carbon nanotubes.