HIGH-FIELD MAGNETORESISTANCE IN GaAs/Ga_0.7Al_0.3As HETEROJUNCTIONS DUE TO ELASTIC AND INELASTIC SCATTERING

D.R. Leadley¹, R.J. Nicholas¹, W. Xu^2,3, F.M. Peeters², J.T. Devreese², J. Singleton^1,4, J.A.A.J. Perenboom⁴, L. van Bockstal⁵, F. Herlach⁵, J.J. Harris⁶ and C.T. Foxon⁷

1. Deptment of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UK
2. Departement Natuurkunde, Universiteit Antwerpen (UIA), Universiteitsplein 1, B-2610 Antwerpen, Belgium
3. Deptment of Theortical Physics, The Australian National University, Canberra, ACT 0200, Australia.
4. Univerisity of Nijmegen, Toerooiveld 1, NL-6525 ED, Nijmegen, The Netherlands
5. Katholieke Universiteit Leuven, Celestijnenlaan 200 D, B-3001, Leuven, Belgium.
6. Department of Electronics and Electrical Engineering, University College London, WC1E 6BT, UK
7. Department of Physics, University Park, Nottingham, NG7 2RD, UK

In this paper we present measurements and calculations which explain the high field magnetoresistance observed up to 30T in GaAs-GaAlAs heterojunctions over the temperature range 1.5K to 300K. The scattering mechanisms that determine the mobility analogue are compared at B=0 and in high field, where it is found that the field and temperature dependence of the Landau level broadening significantly influences the scattering. The calculations, based on the momentum balance equation, include all the scattering processes self consistently in evaluation of both the density of states and resistivity. By this method we are able to obtain good agreement between experiment and theory, both at B=0 and in high magnetic field.

Physical Review B 48, 5457 (1993)