Black Hole Phenomena in Quantum Hall Systems 1: Quasinormal Modes

Point contact geometries in quantum Hall systems have formed excellent probes of quasiparticle scattering. Here, we demonstrate how they can access quasinormal modes – temporally decaying excitations – which are hitherto unexplored in QH settings. On the astronomical scale, quasinormal modes are one of the characteristic signatures of black holes and have played a key role in the recent LIGO detection of black hole mergers. We show how lowest Landau level physics in the presence of a saddle potential, such as at a point contact, can directly simulate the scattering of scalar particles by a black hole spacetime. The S matrix obtained from this scattering problem has poles in the complex plane corresponding to the quasinormal modes. We present the results of Gaussian wavepacket scattering to discern these states in the reflected wavepacket. We also discuss the possible signatures of the quasinormal modes in time-resolved measurements on quantum Hall systems in point contact geometries.