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تسجيل مستخدم جديدLocal magnetism, magnetic order and spin freezing in the nonmetallic metal FeCrAs
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We present the results of x-ray scattering and muon-spin relaxation ($mu^{+}$SR) measurements on the iron-pnictide compound FeCrAs. Polarized non-resonant magnetic x-ray scattering results reveal the 120$^circ$ periodicity expected from the suggested three-fold symmetric, non-collinear antiferromagnetic structure. $mu^+$SR measurements indicate a magnetically ordered phase throughout the bulk of the material below $T_mathrm{N}$=105(5) K. There are signs of fluctuating magnetism in a narrow range of temperatures above $T_mathrm{N}$ involving low-energy excitations, while at temperatures well below $T_mathrm{N}$ behaviour characteristic of freezing of dynamics is observed, likely reflecting the effect of disorder in our polycrystalline sample. Using density functional theory we propose a distinct muon stopping site in this compound and assess the degree of distortion induced by the implanted muon.
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The complex optical properties of a single crystal of hexagonal FeCrAs ($T_N simeq 125$ K) have been determined above and below $T_N$ over a wide frequency range in the planes (along the $b$ axis), and along the perpendicular ($c$ axis) direction. At
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