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Electrical properties of isotopically enriched neutron-transmutation-doped ^{70} Ge:Ga near the metal-insulator transition

Michio Watanabe·Youiti Ootuka·Kohei M. Itoh·Eugene E. Haller
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Abstract

We report the low temperature carrier transport properties of a series of nominally uncompensated neutron-transmutation doped (NTD) ^{70} Ge:Ga samples very close to the critical concentration N_c for the metal-insulator transition. The concentration of the sample closest to N_c is 1.0004N_c and it is unambiguously shown that the critical conductivity exponent is 0.5. Properties of insulating samples are discussed in the context of Efros and Shklovskii's variable range hopping conduction.

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Michio Watanabe, Youiti Ootuka, Kohei M. Itoh, Eugene E. Haller. 1998-11-02. Electrical properties of isotopically enriched neutron-transmutation-doped ^{70} Ge:Ga near the metal-insulator transition. https://doi.org/10.1103/physrevb.58.9851

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