Effect of crystal structure on the magnetic properties of semiconductingCd0.5Mn0.5Te

Single crystals of ${\mathrm{Cd}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ for $0.17\le x\le 0.70$ display a cusp in the susceptibility. Films of ${\mathrm{Cd}}_{0.5}$ ${\mathrm{Mn}}_{0.5}$Te were deposited by sputtering at temperatures ranging from 77 to 1100 K. Films deposited at 300 K and above consist of a mixture of cubic and hexagonal phases. Such films are characterized by a susceptibility cusp at 25 K which is higher than the corresponding single-crystal value ($\simeq 15$ K) although the values of the susceptibility at 4.2 K are very close (4.2×${10}^{-5\mathrm{}}$ emu/g). The most striking result is observed on films deposited at 77 K. These latter films are amorphous semiconductors with an enhanced susceptibility at 4.2 K (as high as 3×${10}^{-4\mathrm{}}$ emu/g) and there is no susceptibility cusp above 4.2 K. The interesting conclusion is that crystallinity is essential to the presence of the susceptibility peak, which is consistent with a recent suggestion that ${\mathrm{Cd}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ is not a canonical spin-glass and is better described by cluster freezing.