Quasi-Two-Dimensional Ferromagnetism in Cr2Te3 and Cr5Te8 Crystals
M. Bester, I. Stefaniuk and M. Kuzma
University of Rzeszów, Faculty of Mathematics and Natural Sciences, S. Pigonia 1, 35-959 Rzeszów, Poland
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The crystal structure of CrTe suggests two-dimensional magnetism in the plane perpendicular to the c axis. It is consistent with the temperature dependence of the g factor and EPR lines width observed. In the present paper we investigate the CrTe alloy which has been prepared by melting of the powdered Cr2Te3 in evacuated quartz ampoule at the temperature 1600 K. ESR spectra were recorded using X-band (9.4 GHz) spectrometer provided with gas nitrogen cryostat. The shape of the EPR line depends strongly on the temperature. In the vicinity of the room temperature the lines become very wide and weak or disappear completely. At lower temperatures the shape of the lines approaches the Dyson function. The asymmetry of lines is attributed to the strong exchange interactions as well as to the semimetal electrical conductivity. Above the room temperature the shape of spectra is characteristic for the paramagnetic phase. Results were addressed based on the model of critical spin fluctuations in two-dimensional Heisenberg magnet proposed by Eremin et al.

DOI: 10.12693/APhysPolA.127.433
PACS numbers: 76.50.+g, 75.50.Cc