Princeton University

School of Engineering & Applied Science

Probing Exotic Phases of Interacting Two-Dimensional Carrier Using One-dimensional Density Modulation

M.A. Mueed
Engineering Quadrangle B327
Thursday, October 27, 2016 - 11:00am to 12:30pm

Clean two-dimensional (2D) electron and hole systems subjected to a perpendicular magnetic field exhibit an array of novel phases. At and near zero field, the 2D carriers typically form a degenerate Fermi gas and occupy a Fermi sea in their ground-state. At higher fields, however, their ground-state can transform into various phases such as the integer and fractional quantum Hall states, Fermi gas of composite fermions (exotic electron-flux quasi-particles), anisotropic stripe (charge density wave) phases, Wigner crystal, etc. The evolution into different phases as a function of field, and in some cases temperature, makes the 2D carrier systems very exciting. We have probed some of these phases by imposing a gentle, one-dimensional density modulation to the 2D system. Here we present our recent results on composite fermions possessing a warped Fermi contour, existence of composite fermions very close to an even-denominator fractional quantum Hall state, reorientation of the parallel field-induced stripe phase and Fermi contour splitting of a 2D electron gas.