Orientation of Metastable EL2 under Uniaxial Stress

Abstract

Results of electrical resistivity and Hall measurements of n-type GaAs under uniaxi al stress along [111] The investigated material was n-type liquid encapsulated Czochralski (LEC) GaAs (n = 3.6 x 10 16 cm-3) with EL2 concentration equal to 4.5 x 10 15 cm-3 . The [111]-oriented sample was placed in an optical cryostat and uniaxial stress up to 700 MPa was obtained with a press spring apparatus. The electrical resistivity and Hall effect in the van der Pauw configuration were measured.We found that while EL2 was in its normal configuration (just after the sample was cooled down in the dark) the sample resistivity very weakly depended on applied stress (see open circles in Fig. 1). After the transformation of EL2 (137)