J an 1 99 7 Experimental evidence of a metal - insulator transition in a half - filled Landau level
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چکیده
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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تاریخ انتشار 1997