# Conduction electron spin-lattice relaxation time in the MgB2 superconductor

## TL;DR

This paper measures the conduction electron spin-lattice relaxation time in MgB2 superconductor across various temperatures and magnetic fields, revealing insights into its electronic structure and relaxation mechanisms.

## Contribution

It introduces a method to measure $T_{1}$ in MgB2 using ESR under microwave excitation, distinguishing contributions from different Fermi surfaces.

## Key findings

- Measured $T_{1}$ as a function of temperature and magnetic field.
- Disentangled contributions from two Fermi surfaces.
- Provided insights into relaxation mechanisms in MgB2.

## Abstract

The spin-lattice relaxation time, $T_{1}$, of conduction electrons is measured as a function of temperature and magnetic field in MgB$_2$. The method is based on the detection of the $z$ component of the conduction electron magnetization under electron spin resonance conditions with amplitude modulated microwave excitation. Measurement of $T_{1}$ below $T_c$ at 0.32 T allows to disentangle contributions from the two Fermi surfaces of MgB$_{2}$ as this field restores normal state on the Fermi surface part with $\pi$ symmetry only.