Two-Dimensional Anderson Localization in Black Phosphorus Crystals Prepared by Bismuth-Flux Method

抄録

The temperature and magnetic field dependence of the electrical resistivity of black phosphorus single crystals prepared by the bismuth-flux method was measured down to 0.5 K in temperature and up to 6 T in magnetic field. While a typical semiconducting behavior of p-type conduction has been observed above about 10 K, the log T-like dependence of the conductivity and the log B dependence of the negative magnetoresistance have been found below 10 K. Results of the field dependence of the magnetoresistance are in good agreement with the theory of the two-dimensional Anderson localization. The whole results are understood by a model that the 3D hole conduction process in the high temperature region is replaced at about 10 K by a 2D electron gas confined near the surface.