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تسجيل مستخدم جديدMagnetic properties of Mn-doped Bi$_2$Se$_3$ compound: temperature dependence and pressure effects
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Magnetic susceptibility $chi$ of Bi$_{2-x}$Mn$_{x}$Se$_3$ ($x = 0.01-0.2$) was measured in the temperature range $4.2-300$ K. For all the samples, a Curie-Weiss behaviour of $chi(T)$ was revealed with effective magnetic moments of Mn ions corresponding to the spin value S=5/2, which couple antiferromagnetically with the paramagnetic Curie temperature $Thetasim -50$ K. In addition, for the samples of nominal composition $x$ = 0.1 and 0.2 the effect of a hydrostatic pressure $P$ up to 2 kbar on $chi$ has been measured at fixed temperatures 78 and 300 K that allowed to estimate the pressure derivative of $Theta$ to be d$Theta$/d$Psim-0.8$ K/kbar. Based on the observed behaviour of $Theta$ with varied Mn concentration and pressure, a possible mechanism of interaction between localized Mn moments is discussed.
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