## Visit to to the AMOPP group at UCL

Today I was invited to give a talk to the AMOPP group at UCL. While I was visiting I was given a lab tour of the LCN, and I got to see all their fancy stainless steel lab equipment including big magnets and other stuff to move and measure small cold things.  During the visit I heard about the latest stuff they are doing there, including some very exciting implementations of electrical spin-trap readout of coherence in silicon.

I heard from the group of Sougato Bose, and I learnt about some counterintuitive results showing that after a quench of interactions in the XXZ chain there can be a substantial generation of entanglement from an initial thermal state. I also heard about the some other results about entanglement generation after a quench, but this time where only one or two interactions are quenched. Both of these papers are intimately linked with how quasiparticles propagate through interacting quantum spin systems and, by focussing on entanglement generation, expose subtle transport physics in these models. Eg. check out figure 4 in this paper where some kind of interesting transition (probably not a quantum phase transition) is occurring at $\Delta = -0.5$.

The slides for the talk I gave are here. I spoke about the some of the known results concerning the computational complexity of simulating interacting quantum systems, in particular, quantum spin systems.