The Magnetic-Field Dependent Phonon-Like FIR Absorption in Modulation Doped CdMnTe/CdMgTe quantum Well Structures.
Abstract
Spin-dependent phonon had been reported in several magnetic semiconductors. This unique phonon mode is resulted from an ion-position dependent spin Hamiltonian. This mode can be either infrared or Raman active. However, such modes were never observed in the diluted magnetic semiconductors. We have investigated a series of CdMnTe/CdMgTe QW samples with Mn concentration ranged from 0 to 3.9% up to 33T and found an IR absorption near 125cm-1. The intensity of this mode increases rapidly with increasing magnetic field, while the energy increases only several wavenumbers. This behavior resembles that of the spin-dependent phonon mode. The unique behavior of the spin-dependent phonon mode was induced by a magnetic transition with decreasing temperatures. In the current studies, however, similar behavior is induced by applying magnetic field. Besides 125cm-1 mode, we have also observed two new IR absorptions in addition to the electron cyclotron resonance (CR). The intriguing disappearance of CR at high magnetic field and the stimulating behavior of these two new modes will be discussed.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2007
- Bibcode:
- 2007APS..MARU43002T