Physics (Internal)

Finite-depth quantum circuits and many-body localization

This event is part of the Biophysics/Condensed Matter Seminar Series.

Dynamics of disordered, quantum many-body systems provide a classic physical setting for the breakdown of quantum ergodicity, known as many-body localization (MBL). In this novel out of equilibrium quantum phase, the many-body system acts as a local memory even in highly excited states which is characterized by an emergent integrability. Utilizing the local conservation laws I will present an efficient representation of unitary circuits approximating the full spectrum of MBL eigenstates.

I will show how the approximating circuit can be used to construct the algebra of all the exact l-bit operators and probe their behaviour close to the MBL-thermal transition in one dimension. Furthermore, the circuit can be generalized to two dimensions to estimate the location of the “MBL transition” in the Bose-Hubbard model which was putatively observed in recent cold atomic experiments.