Magnetic Order and Magnetic Inhomogeneities in SnCrTe-PbCrTe Solid Solutions

Abstract

We present the studies of structural, electrical and magnetic properties of bulk Sn1−x−y PbxCry Te mixed crystals with chemical composition 0.18 ≤ x ≤ 0.35 and 0.007 ≤ y ≤ 0.071. The magnetometric studies indicate that for the high Cr-content, y = 0.071, the alloy shows ferromagnetic alignment with the Curie temperature, TC, around 265 K. The Cr5Te8 clusters are responsible for the ferromagnetic order. At low Cr content, y ≈ 0.01, a peak in the ac magnetic susceptibility identied as the cluster-glass-like transition is observed at a temperature about 130 K. The cluster-glass-like transition is likely due to the presence of Cr2Te3 clusters in the samples with y ≈ 0.01. The transport characterization of the samples indicated strong metallic p-type conductivity with relatively high carrier concentration, n > 10 20 cm −3 , and carrier mobility, µ > 150 cm 2 /(V s).

Magnetic Interactions in IV–VI Diluted Magnetic Semiconductors

“…We also experimented with adding Pb, Sn, or Eu to Ge 1Àx Mn x Te. [105][106][107] Magnetic properties of such quaternary compounds were similar to those described above for Ge 1Àx Cr x Te codoped with Pb and Eu.…”

“…The magnetic properties of Sn 1− x − y Pb y Cr x Te and Sn 1− x − y Eu y Cr x Te crystals were similar. The magnetic susceptibility versus temperature for the Sn 1− x − y Pb y Cr x Te samples with x ≈ 0.01 and Sn 1– x − y Eu y Cr x Te with x < 0.07 showed the presence of a well‐defined peak at temperatures around 120–140 K. [ 101,102 ] This effect was identified as the appearance of a cluster–spin glass freezing of the Cr 2 Te 3 grains. The possible presence of such grains was confirmed by the diffraction patterns.…”