Quantum Phase transitions

In two new publications (here and here) the Fauseweh group explores quantum phase transitions in- and out-of-equilibrium.

In the first article we theoretically investigate light pulse driven dynamics in a Kondo lattice system and demonstrate, that that light can dehybridize the local Kondo screening and induce oscillating magnetic order out of a previously paramagnetic state. This fundamental change in the behaviour of the system can be traced with time- and angle-resolved photoemission spectroscopy (t-ARPES).

In the second article we explore how to use quantum computers to detect phase transitions in magnetic systems. We demonstrate that fidelities and Hellmann-Feynman forces are much more robust against noise than energy expectation values on real devices.