INVESTIGATION OF COMPENSATED GALLIUM ARSENIDE IN STRONG MAGNETIC FIELDS.

An investigation was made of the magnetoresistance of compensated gallium arsenide in magnetic fields 50 less than equivalent to H less than equivalent to 150 kOe at helium temperatures. The magnetic-field-induced rise of the resistivity of samples with an initial free-electron density n//0 greater than 4. 8 multiplied by (times) 10**1**6 cm** minus **3 approximately equals n//c, corresponding to the Mott transition in the limit H yields O, was entirely due to a reduction in the electron mobility resulting from the lifting of the electron-gas degeneracy in a magnetic field. In the case of the samples with n//0 less than n//c the resistivity increased because of a reduction in the mobility and free-electron density due to an additional localization in potential wells.