Abstract
Fractional quantum Hall (FQH) effect arises when a 2D electron gas is subjected to very high magnetic fields and ultra-low temperatures. The hallmark of the effect is quantized Hall resistance and zero longitudinal resistance. Some of the collective electron excitations in the FQH state are predicted to have exotic properties that could enable topological quantum computation. To access delicate FQH physics, it is crucial to be able to conduct transport measurements at low noise levels and ultra-low electron temperatures (<25mK). This project contributes to the experimental research on FQH states in graphene by redesigning several measurement devices components to enable such measurements. Specifically, we upgraded one of the measurement probes with a set of home-made filters. These filters include several stages of band-pass signal filters used for reducing the noise and a gold meander wafer for obtaining low electron temperature.
