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High-field irreversible moment reorientation in the antiferromagnet Fe$_{1.1}$Te

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 نشر من قبل William Knafo
 تاريخ النشر 2012
  مجال البحث فيزياء
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Magnetization measurements have been performed on single-crystalline Fe$_{1.1}$Te in pulsed magnetic fields $mathbf{H}perpmathbf{c}$ up to 53 T and temperatures from 4.2 to 65 K. At $T=4.2$ K, a non-reversible reorientation of the antiferromagnetic moments is observed at $mu_0H_R=48$ T as the pulsed field is on the rise. No anomaly is observed at $H_R$ during the fall of the field and, as long as the temperature is unchanged, during both rises and falls of additional field pulses. The transition at $H_R$ is reactivated if the sample is warmed up above the N{e}el temperature $T_Nsimeq60$ K and cooled down again. The magnetic field-temperature phase diagram of Fe$_{1.1}$Te in $mathbf{H}perpmathbf{c}$ is also investigated. We present the temperature dependence of $H_R$, as well as that of the antiferromagnetic-to-paramagnetic borderline $H_c$ in temperatures above 40 K.

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