Detta är en digital seminarieserie i kondenserade materiens fysik och atomfysik, med syfte att koppla samman forskare från olika nordiska universitet. Samtalen är informella och ska inspirera till diskussioner och interaktioner.
In this talk, I will introduce the dynamical phenomenon of timescale separation known as metastability in the context of Markovian open quantum systems. Metastability arises, among others, in proximity to first-order phase transitions and leads to the existence of multiple long-lived states whose changes are negligible over a pronounced period of time, before their unavoidable asymptotic relaxation to a unique stable state. I will discuss metastability both in the average and stochastic dynamics of open quantum systems, with special focus on signatures which can be uncovered in numerical simulations or experiments. In average dynamics, those signatures depend on whether metastable states can be characterised in terms of classical degrees of freedom, or a more general quantum description is needed. In the context of stochastic dynamics arising from continuous monitoring of open quantum systems, by considering quantum trajectories described by quantum reset processes, we will see both cases can have classical but distinct analogues. Classical metastable phenomenology (fast relaxation into distinct phases and slow transitions between) will be shown to hold for the former, while for the latter, a continuous evolution to occur within a slow manifold (that can also be made fast thanks to underlying quantum degrees of freedom).
Zoom-länk: https://nordita.org/zoom/nvcms