Magnetic and magneto-optical properties in diluted magnetic semiconductors: Cd1-x-yMnxFeyTe single crystals

We investigated the magneto-optical properties of diluted magnetic semiconductor Cd1-x-yMnxFeyTe (x similar to 0.38) single crystals grown using a vertical Bridgman method. Faraday rotation as a function of photon energy with various Fe compositions for CdMnFeTe in the temperature range of 10-300 K has been measured. The Verdet dispersion curves were enhanced near the fundamental band gap energy. The Verdet constant becomes larger since the effect of the sp-d exchange interaction is enhanced as the temperature is lowered. At 10 K, the Verdet constants of the Faraday rotation for the samples with y = 0, 0.017, 0.038, and 0.058 were observed to be -0.93, -1.36, -1.65, and -1.94 deg/G cm at 610 nm, respectively. The Verdet constant showed a maximum for the sample with y = 0.058, and the value is approximately four times larger than that of the Cd0.62Mn0.38Te crystal, and this behavior agrees well with that of the magnetic susceptibility. (C) 2006 Elsevier B.V. All rights reserved.