DIRECT COMPARISON OF THE QUANTIZED HALL RESISTANCE IN GALLIUM-ARSENIDE AND SILICON

Using an ultrasensitive, cryogenic, current-comparator bridge the quantized Hall resistance R(H)(2) in a GaAs/AlGaAs heterostructure has been compared directly with R(H)(4) in a silicon MOSFET. The measurements show that R(H)(2;GaAs)/R(H)(4;Si) = 2[1 -0.22(3.5) x 10(-10)]. Within the 1-sigma-combined uncertainty of +/- 3.5 x 10(-10) the result suggests that the quantized Hall resistance is a universal quantity, independent of the host lattice and Landau-level index, and is probably equivalent to h/e2, the relationship predicted theoretically.