The spin-resonance amplitude of conduction electrons in a cubic crystal has been calculated keeping terms up to fourth order in the wave vector k in the 2×2 effective-mass Hamiltonian. Apart from corrections to the magnetic dipole amplitude, we find that the terms γ0μB(σxB0xkx2 +σyB0yky2+σzB0zkz2) and g’’μB{σ⋅k, B0⋅k} yield electric dipole amplitudes proportional to k⋅B0. While in the ordinary Voigt and cyclotron-resonance-active Faraday configurations only the γ0 term is effective, in the cyclotron-resonance-inactive Faraday configuration both the γ0 and g’’ terms contribute. We have calculated the angular dependence of the γ0 amplitude for arbitrary crystal orientations, the g’’ amplitude being isotropic. In narrow-band-gap materials the admixture of hole states into the electron eigenstates also contributes an isotropic electric dipole spin-flip amplitude proportional to k⋅B0, which is distinct from those mentioned.
EFFECT OF NONPARABOLICITY ON THE CONDUCTION-ELECTRON SPIN-RESONANCE IN CUBIC SEMICONDUCTORS
LA ROCCA, Giuseppe Carlo;
1989
Abstract
The spin-resonance amplitude of conduction electrons in a cubic crystal has been calculated keeping terms up to fourth order in the wave vector k in the 2×2 effective-mass Hamiltonian. Apart from corrections to the magnetic dipole amplitude, we find that the terms γ0μB(σxB0xkx2 +σyB0yky2+σzB0zkz2) and g’’μB{σ⋅k, B0⋅k} yield electric dipole amplitudes proportional to k⋅B0. While in the ordinary Voigt and cyclotron-resonance-active Faraday configurations only the γ0 term is effective, in the cyclotron-resonance-inactive Faraday configuration both the γ0 and g’’ terms contribute. We have calculated the angular dependence of the γ0 amplitude for arbitrary crystal orientations, the g’’ amplitude being isotropic. In narrow-band-gap materials the admixture of hole states into the electron eigenstates also contributes an isotropic electric dipole spin-flip amplitude proportional to k⋅B0, which is distinct from those mentioned.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
