Anisotropy of conducting p states and ¹¹B nuclear spin-lattice relaxation in Mg_1-xAl_xB₂

Authors

Kirill D. Belashchenko, University of Nebraska-LincolnFollow
Vladimir B. Antropov, Ames Laboratory, US Department of EnergyFollow
S.N. Rashkeev, Vanderbilt University, Nashville, Tennessee

Document Type

Article

Date of this Version

8-28-2001

Comments

Published in PHYSICAL REVIEW B, VOLUME 64, 132506. ©2001 The American Physical Society. Used by permission.

Abstract

We calculated the nuclear spin-lattice relaxation rate in the Mg_1-xAl_xB₂ system and found that the orbital relaxation mechanism dominates over the dipolar and Fermi-contact mechanisms in MgB₂, whereas in AlB₂ due to a smaller density of states and strong anisotropy of boron p orbitals the relaxation is completely determined by Fermi-contact interaction. The results for MgB₂ are compared with existing experimental data. To validate the theory, nuclear resonance experiments for the studied diboride alloy system are needed.