Local magnetism, magnetic order and spin freezing in the ‘nonmetallic metal’ FeCrAs

Optical properties and electronic structure of the nonmetallic metal FeCrAs

A. Akrap,1,* Y. M. Dai,1 W. Wu,2 S. R. Julian,2,3 and C. C. Homes1,† 1Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA 2Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario, Canada M5S 1A7 3Canadian Institute for Advanced Research, 180 Dundas Street West, Suite 1400, Toronto, Canada M5G 1Z8 (Rec...

Spin freezing and magnetic inhomogeneities in bilayer manganites.

We have performed a muon spin rotation study on polycrystalline samples of electron-doped layered manganites, La2-2xSr1+2xMn2O7 (0.4< or =x<1), in order to investigate the local magnetic structure and spin dynamics. Our results provide evidence for phase separation into A-type antiferromagnetic and charge-ordered phases for x=0.52 and spin freezing at low temperatures (T<100 K) for 0.52< or =x<...

Cooperative freezing in spin glasses and magnetic nanostructures

Local Spin Glass Order in 1 D

– We study the behavior of one-dimensional Kac spin glasses as a function of the interaction range. We verify by Monte Carlo numerical simulations the crossover from local mean-field behavior to global paramagnetism. We investigate the behavior of correlations and find that in the low-temperature phase correlations grow at a faster rate then the interaction range. We completely characterize the...

Magnetism in spin models for depleted honeycomb-lattice iridates: Spin-glass order towards percolation

Iridates are characterized by a fascinating interplay of spin-orbit and electron-electron interactions. The honeycomb-lattice materials A2IrO3 (A = Na,Li) have been proposed to realize pseudospin-1/2 Mott insulating states with strongly anisotropic exchange interactions, described by the Heisenberg-Kitaev model, but other scenarios involving longer-range exchange interactions or more delocalize...