Giant Faraday Rotation in CdTe Spin-Doped with Rare Earth Ions

Abstract

Subject classification: 78.20.Ls; S8.13The Faraday rotation of CdTe single crystals doped with Eu, Gd, Dy rare earth elements has been studied. The largest enhancement of the Faraday rotation near the fundamental absorption edge has been found for the case of dysprosium dopant. At liquid helium temperature the Verdet constant of CdTe : Dy with concentration N Dy = 10 20 cm --3 is two orders of magnitude larger than the values for pure CdTe. At room temperature, the sign of the Faraday rotation changes depending on photon energy and impurity concentration. Tending towards saturation effects has been found in the magnetic field dependence of the Faraday rotation. All observed features in spectral, concentration, temperature and magnetic field dependence of the Faraday effect in CdTe : Dy crystals suggest a strong spin exchange interaction between f electrons of rare earth ions and s, p band carriers.

EDS, XRD and Raman Scattering Study of Dy Ion Implanted CdTe Polycrystalline Thin Films

“…In semiconductor crystals, the fairly compact 4f open shell makes RE impurities retain their atomic characteristics bring on abundant useful magnetic or optical properties. It has been reported the Faraday effect represented by the giant Faraday rotation in CdTe:Dy crystals [3]. In this paper we further study experimentally the relevant effect of RE impurities on the structure and optical property of CdTe:Dy PTF prepared by homemade CSS system.…”

Optical and magnetooptical study of CdTe crystals doped with rare earth ions

“…For this class of materials spin-related phenomena such as enhanced Zeeman spin splitting of the band states and giant Faraday rotation which are due to spin exchange interactions between band carriers and magnetic ions have been revealed. In particular, it has been reported of magnetooptical features for case of Cd 1−x Gd x Te solid solutions [4] and doped CdTe:Dy crystals [5]. Nevertheless, large magnetooptical effects induced by the exchange interaction between electrons and magnetic ions in rare earth based semimagnetic semicoductors are not well understood yet.…”