Interplay between nematicity and Bardasis-Schrieffer modes in the short-time dynamics of unconventional superconductors

TL;DR

This paper investigates how nematicity influences collective modes in unconventional superconductors, revealing hybridization of modes and effects on oscillation damping, with implications for interpreting pump-probe experiments.

Contribution

It demonstrates the hybridization of Bardasis-Schrieffer and nematic modes and their impact on short-time dynamics in systems with competing orders.

Findings

Hybridization of Bardasis-Schrieffer and nematic modes in symmetric states.

Nematic interaction suppresses damping of collective oscillations.

Order parameter oscillations depend on competition between pairing symmetries.

Abstract

Motivated by the recent experiments suggesting the importance of nematicity in the phase diagrams of ironbased and cuprate high-Tc superconductors, we study the influence of nematicity on the collective modes inside the superconducting state in a non-equilibrium. In particular, we consider the signatures of collective modes in short-time dynamics of a system with competing nematic and s- and d-wave superconducting orders. In the rotationally symmetric state, we show that the Bardasis-Schrieffer mode, corresponding to the subdominant pairing, hybridizes with the nematic collective mode and merges into a single in-gap mode, with the mixing vanishing only close to the phase boundaries. For the d-wave ground state, we find that nematic interaction suppresses the damping of the collective oscillations in the short-time dynamics. Additionally, we find that even inside the nematic s+d-wave superconducting state, a Bardasis-Schrieffer-like mode leads to order parameter oscillations that strongly depend on the competition between the two pairing symmetries. We discuss the connection of our results to the recent pump-probe experiments on high-Tc superconductors.