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arXiv · 0704.0466

Conduction electron spin-lattice relaxation time in the MgB2 superconductor

F. Simon·F. Murányi·T. Fehér·A. Jánossy·L. Forró·C. Petrovic·S. L. Bud'ko·P. C. Canfield
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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 $π$ symmetry only.

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F. Simon, F. Murányi, T. Fehér, A. Jánossy, L. Forró, C. Petrovic, S. L. Bud'ko, P. C. Canfield. 2007-04-03. Conduction electron spin-lattice relaxation time in the MgB2 superconductor. https://doi.org/10.1103/physrevb.76.024519

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