| 1. |
- BAJOREK, A, et al.
(författare)
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ON EXCHANGE MECHANISM IN HG1-XMNXS
- 1994
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Ingår i: Journal of Magnetism and Magnetic Materials. - 0304-8853 .- 1873-4766. ; 131, s. 363-368
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Tidskriftsartikel (refereegranskat)abstract
- The magnetic susceptibility of Hg0.95Mn0.05S and Hg0.90Mn0.10S was measured by the SQUID technique. The experimental data were compared with the extended nearest neighbour pair approximation (ENNPA) calculation. The long range exchange interaction J = J(NN)R(-n), with the exponent n = 4, was found for both samples. The nearest neighbour exchange integral J(NN) was found to be around two times smaller than the effective exchange integral J(eff). The small value of the exponent n, which is a characteristic of the narrow gap semimagnetic semiconductors (SMSC’s), as well as the small J(NN)/J(eff) ratio, show the importance of a long-range exchange mechanism.
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| 2. |
- SPASOJEVIC, V, et al.
(författare)
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MAGNETIC-SUSCEPTIBILITY OF THE SEMIMAGNETIC SEMICONDUCTOR HG1-XMNXS
- 1993
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Ingår i: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 118, s. 152-158
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Tidskriftsartikel (refereegranskat)abstract
- The magnetic susceptibility of Hg1-xMnxS (x = 0.05, 0.10, 0.20, 0.30) has been measured in a SQUID magnetometer (T = 2-250 K) in a magnetic field of 9 kG. The high-temperature susceptibility of Hg1-xMnxS was found to behave in accordance with the Curie-Weiss law. From chi(T) measurements, for the first time, the microscopic parameter J1/k(B) = -(6.3 +/- 0.1) K (effective exchange integral) has been obtained. A spin S = 2.48 +/- 0.09, close to its atomic value S = 5/2, was also found. Low-temperature susceptibility measurements show that the sample with the highest Mn-concentration (x = 0.30) exhibits a difference between field-cooled and zero-field-cooled susceptibility signalling a spin-glass phase transition at about 4 K. As Hg1-xMnxS is the last uninvestigated alloy from the A1-xIIMnxBVI group, a complete review of experimental values (J1/k(B)) is also given.
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