IMPURITIES IN GaAlAs-GaAs HETEROJUNCTIONS METASTABLE CHARACTER OF Si STATES AND MAGNETODONORS A. RAYMOND, R. PIOTRZKOWSKI, J.L. ROBERT, S. AZEMA, M. KUBISA, W. ZAWADZKI, L. LITWIN-STASZEWSKA et J.P. ANDRÉ J. Phys. Colloques, 48 C5 (1987) C5-243-C5-246 DOI: 10.1051/jphyscol:1987551