Bulletin of the American Physical Society
APS March Meeting 2018
Monday–Friday, March 5–9, 2018; Los Angeles, California
Session G60: Poster Session I
Tuesday, March 6, 2018
LACC Room: West Hall A
Abstract: G60.00193 : 55Mn and 27Al NMR investigation of YMn4Al8 single crystals
(Gwangju Inst of Sci & Tech.)
55Mn and 27Al Nuclear magnetic resonance (NMR) measurements are performed on a single crystal of YMn4Al8 at 8 T down to 4 K. The NMR spectrum, Knight shift, linewidth, spin–lattice relaxation rate 1/T1, and spin–spin relaxation rate 1/T2 are measured as a function of temperature for the c-axis parallel and perpendicular to the magnetic field. The 55Mn NMR spectrum exhibits five broad satellites due to nuclear quadrupole interaction for a nuclear spin of I = 5/2. The 27Al NMR spectrum exhibits two different sites, Al-A and Al-B, with five satellites for each site due to nuclear quadrupole interaction for I = 5/2. Based on the broader linewidths of the Al-B spectra, the Al-B site turns out to be closer to the Mn 3d electrons. The local electronic structures at the Mn and Al sites measured by NMR are almost isotropic for the c-axis parallel and perpendicular to the magnetic field. The temperature dependence of the Knight shifts and the Korringa product 1/T1T, as well as the magnetic susceptibility, show a large decrease at low temperature, indicating the opening of a pseudo-gap in YMn4Al8. The Knight shift scales with the susceptibility, from which the hyperfine coupling constant is extracted and found to be 55A = −140 kOe/μB.
The American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics.
1 Physics Ellipse, College Park, MD 20740-3844
Editorial Office 1 Research Road, Ridge, NY 11961-2701 (631) 591-4000
Office of Public Affairs 529 14th St NW, Suite 1050, Washington, D.C. 20045-2001 (202) 662-8700