The next AIP theoretical physics seminar speaker will be Weijian Chen, Washington University in St. Louis, from 11am AEDT Thursday Nov 18.

Title: Dynamical control of a non-Hermitian superconducting qubit

Abstract: Open systems with loss or gain, described by effective non-Hermitian Hamiltonians, have attracted great attention in recent years. Such systems in general have complex energies and nonorthogonal eigenstates, and their degeneracies are known as exceptional points. The complex energies near an exceptional point form a Riemann manifold, whose topology enables a new control method and has found applications in energy transport and mode switch. In this talk, I will present our recent work on dynamical control of a non-Hermitian superconducting qubit. By varying the Hamiltonian parameters in real time to encircle an exceptional point, we observe that the qubit initialized at one eigenstate is transported to another eigenstate. We further study the chiral geometric phase associated with quantum coherent state transport on the Riemann manifold. In addition, I will discuss non-Hermitian physics based on Liouvillian superoperators, which goes beyond the existing Hamiltonian formalism and allows us to observe decoherence-induced exceptional points.

Register in advance for this webinar here

Please note that the full list of talks in this series can be found at the YouTube channel