SIZE DEPENDENCE OF THE CHANGEOVER FROM GEOMETRIC TO MAGNETIC CONFINEMENT IN IN0.53GA0.47AS INP QUANTUM WIRES/

Photoluminescence studies on deep-etched In0.53Ga0.47As/InP quantum wi res of several lateral widths L(x) greater than or equal to 25 M1 have been performed in magnetic fields up to B=8.0 T. By optically generat ing a dense electron-hole plasma in the quantum wires, emission from d ifferent lateral subbands has been observed. With the magnetic field a ligned along the growth direction, a changeover of the characteristic length scale that determines the carrier quantization energies from th e lateral wire width to the cyclotron length is observed with increasi ng B. This transformation is observed when the cyclotron energy become s comparable to the quantization energy. The magnetic held at which th is transition occurs increases proportionally to the inverse of the sq uare of the wire width in agreement with theoretical calculations.