Quasi Particle Tunneling in the Fractional Quantum Hall Regime Author:

tjv380 The fractional quantum Hall effect occurs in clean two dimensional electron gases subjected to a perpendicular magnetic field. This rich system is 34 years after its discovery still not fully understood. Several problems still remain open after many years of serious attention from both experimentalists and theorists. It is therefore wroth investigating the seemingly basic questions, from which we still have a lot to learn. In this thesis investigations of excitations in the fractional quantum Hall effect is presented. In Chapter 1 I give an introduction to the two dimensional electron gas, the classical Hall effect and the quantum Hall effect. Chapter 2 is devoted to the quantum point contact (QPC). Firstly I give an introduction to the basics of the QPC, followed by data showing many robust conductance steps at zero bias and a link between the 0.7 structure in the first subband and finite bias features in the second. Quasi particle tunneling can provide us with crucial information about the origi