Quasiparticle Relaxation Dynamics in Two Distinct Gap Structures: La$_{0.67}$Ca$_{0.33}$MnO$_{3}$ and LaMnO$_{3}$

TL;DR

This study investigates how quasiparticle and spin relaxation dynamics vary with temperature and magnetic field in two manganites with different gap structures, revealing the influence of pseudogap and Jahn-Teller gap on relaxation processes.

Contribution

It provides new insights into the coupled charge, spin, and lattice dynamics in manganites with distinct electronic gap structures using pump-probe spectroscopy.

Findings

Relaxation dynamics are governed by a pseudogap in La0.67Ca0.33MnO3.

LaMnO3 exhibits temperature-independent Jahn-Teller gap effects.

Charge, spin, and lattice dynamics are strongly correlated with gap structures.

Abstract

The spin and quasiparticle relaxation dynamics in La$_{0.67}$Ca$_{0.33}$MnO$_{3}$ and LaMnO$_{3}$ single crystals and thin films is investigated as a function of temperature and magnetic field by pump-probe spectroscopy. The unusually slow spin-lattice relaxation dynamics is governed by the temperature- and magnetic field- dependent pseudogap in La$_{0.67}$Ca$_{0.33}$MnO$_{3}$, and by the temperature-independent Jahn-Teller gap in LaMnO$_{3}$. Our results show that the coupled dynamics of charge, spin and lattice is strongly correlated with the distinct gap structures in these manganites.