Influence of Hole-Phonon Coupling on Thermodynamic and Magnetic Properties of Diluted Semiconductor: Ga_1-xMn_xAs in Quantum Dots.

Owing to the possible future importance of hole-based quantum structures, the studies on single/ multiple hole quantum dots have picked momentum in recent years e.g. Delaforce et. al. have recently explored experimentally probe the low temperature transport in single hole quantum dots. van-Riggelen et. al. have studied 2-D quantum dots array with each quantum dot having a single hole as charge career as possible means for quantum computation. This point is validated as the single hole state in a semiconductor QD is better suited for quantum information [3]. In this work the thermodynamic and magnetic properties of a two-holes parabolic quantum dot are studied in the presence of hole-hole and hole-phonon interactions in the range of temperature from 0 K to 50 K and in magnetic fields varying from -5 to 5 T. Calculations of energy levels of two-holes states have been performed with a resolution of the Schrödinger’s equation and all thermodynamic functions are derived by using the canonical ensemble. Our formalism’s numerical calculation is essentially applied to dilute ferromagnetic semiconductors Ga1-x MnxAs containing 3% Mn.

The founded results show that the magnetic an thermodynamic properties are influenced by the magnetic field, hole-phonon and hole-hole interactions, and the confinement. The analysis of magnetization and susceptibility justifies that the ferromagnetic transition temperature can be increased as a result of increasing of magnetic field which is in a good agreement with previous works.