Landau and spin levels in InAs quantum wells resolved with inplane and parallel magnetic fields

High-mobility InAs quantum wells embedded between AlSb barriers are investi gated by transport experiments at T = 80 mK in tilted magnetic fields. For magnetic fields applied normal to the sample surface the Landau level split ting is much larger than the spin splitting and minima are observed in the low-field Shubnikov-de Haas (SdH) oscillations predominantly at even intege r filling factors. As the magnetic field is tilted away from the sample nor mal the spin splitting is enhanced relative to the Landau level splitting. We can observe SdH-like oscillations up to tilt angles where the spin split ting exceeds the Landau splitting by a factor of 3. From the angles at whic h spin levels of adjacent Landau levels can be made to coincide we can dedu ce a value for gm*, the effective electron g-factor times the effective mas s. (C) 1998 Elsevier Science B.V. All rights reserved.