Photoluminescence and magneto-transport of wide InGaAsInP modulation doped quantum wells

Abstract

A photoluminescence (PL) study of 700Å wide modulation doped InGaAsInP quantum wells in magnetic fields up to 10 Tesla, is reported. PL from the lowest electron sub-bands, localised in the space charge potentials at the two sides of the QW, and from higher delocalised sub-bands extending across the whole width of the QW, is observed. The performance of simultaneous Quantum Hall Effect (QHE), Shubnikov-de-Haas and PL measurements is found to be crucial to obtain a reliable understanding of the behaviour of the PL spectra in magnetic field. In particular the QHE provides direct information on the number of filled sub-bands and Landau levels in a complicated system of total carrier density ∼10 12 cm −2, containing several populated electronic sub-bands.