# First order Fermi surface topological (Lifshitz) transition in an interacting two-dimensional Rashba Fermi liquid

## TL;DR

This paper investigates how interactions influence the Lifshitz transition in a 2D Rashba Fermi liquid, revealing a first-order transition driven by interactions, with implications for experimental systems like BiTeI.

## Contribution

It demonstrates that interactions induce a first-order Lifshitz transition in a 2D Rashba Fermi liquid, extending understanding beyond non-interacting models.

## Key findings

- Interactions cause a first-order transition at zero temperature.
- The transition is more pronounced with spin-orbit coupling.
- Results are supported by perturbation theory and self-consistent approximations.

## Abstract

We study the Fermi surface topological transition of the pocket-opening type in a two dimensional Fermi liquid with spin-orbit coupling of Rashba type. We find that the interactions, far from instabilities, drive the transition first order at zero temperature surprisingly in a more pronounced way than in the case of interacting Fermi liquid without spin-orbit coupling. We first gain insight from second order perturbation theory in the self-energy. We then extend the results to stronger interaction, using the self-consistent fluctuation approximation. We discuss existing experimental work on the system BiTeI and suggest further experiments in the light of these results .