Metal-insulator transition in a 2-dimensional system with an easy spin axis
نویسنده
چکیده
The low-temperature resistivity of a SiGe 2-dimensional hole gas has been studied using the gate controlled carrier density as a parameter. A metal-insulator transition is seen in both the temperature and the electric field behaviour. Values of 1 for the dynamical exponent and 2.85 for the correlation length exponent are obtained from scaling plots. No quenching of the metallic phase in a parallel magnetic field is observed. Since in our system there is an easy axis for magnetization, this result supports the hypothesis that the transition is related to spin interactions.
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