OSCILLATIONS OF INTERSUBBAND ELECTRON RELAXATION IN A GAAS ALXGA1-XASWIDE SINGLE-QUANTUM-WELL NEAR THE SINGLE-LAYER TO DOUBLE-LAYER TRANSITION/

We present the photoluminescence (PL) and transport study of an electr on system confined in a high-quality wide single quantum well at T gre ater than or equal to 60 mK and B less than or equal to 14 T. Near the single-to double-layer transition, if only one electron layer/subband is occupied in equilibrium, strong magneto-oscillations of the second -subband PL intensity with maxima around odd electron filling factors are observed at low temperatures less than or equal to 600 mK. The sha pe of the oscillation maxima depends on intersubband energy spacing. T he observed oscillations are shown to originate from the electron inte rsubband relaxation determined by the relative spin orientation of the initial and final electron states.