MAGNETOOPTICAL ABSORPTION-SPECTRA AND SELF-SIMILARITY OF GAAS-(GA,AL)AS QUASI-PERIODIC FIBONACCI SUPERLATTICES UNDER INPLANE MAGNETIC-FIELDS

A theoretical study of the effects of in-plane magnetic fields on the interband optical absorption spectra of quasiperiodic GaAs-(Ga,Al)As F ibonacci superlattices is presented within the effective-mass approxim ation. The electron-envelope wave functions and magnetic subbands are obtained by an expansion in harmonic-oscillator wave functions. The th eoretical optical absorption spectra are calculated for magnetic field s related by integer powers of the golden mean tau =(1 + root 5)2. It is unambiguously shown that, for magnetic-field values scaled by tau(2 n), the corresponding optical absorption spectra essentially exhibit a self-similar behavior, with the width of the peaks increasing linearl y with the field, in agreement with the experimental results by D. Toe t, M. Potemski, Y. Y. Wang, J. C. Maan, L. Tapter, and K. Ploog [Phys. Rev. Lett. 66, 2128 (1991)]. (C) 1995 American Institute of Physics.