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Experimental evidence of a metal-insulator transition in a half-filled Landau level

C. -T. Liang·J. E. F. Frost·M. Y. Simmons·D. A. Ritchie·M. Pepper
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Abstract

We have measured the low-temperature transport properties of a high-mobility front-gated GaAs/Al_{0.33}Ga_{0.67}As heterostructure. By changing the applied gate voltage, we can vary the amount of disorder within the system. At a Landau level filling factor $ν=1/2$, where the system can be described by the composite fermion picture, we observe a crossover from metallic to insulating behaviour as the disorder is increased. Experimental results and theoretical prediction are compared.

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C. -T. Liang, J. E. F. Frost, M. Y. Simmons, D. A. Ritchie, M. Pepper. 1997-01-09. Experimental evidence of a metal-insulator transition in a half-filled Landau level. https://doi.org/10.1016/s1386-9477(98)00018-6

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