ICTS:30892

Video URL

Open quantum systems in the ultrastrong coupling limit

Open quantum systems in the ultrastrong coupling limit

(2025). Open quantum systems in the ultrastrong coupling limit. SciVideos. https://youtube.com/live/a3os9lYDC-E

Open quantum systems in the ultrastrong coupling limit. SciVideos, Feb. 04, 2025, https://youtube.com/live/a3os9lYDC-E 

          @misc{ scivideos_ICTS:30892,
            doi = {},
            url = {https://youtube.com/live/a3os9lYDC-E},
            author = {},
            keywords = {},
            language = {en},
            title = {Open quantum systems in the ultrastrong coupling limit},
            publisher = {},
            year = {2025},
            month = {feb},
            note = {ICTS:30892 see, \url{https://scivideos.org/index.php/icts-tifr/30892}}
          }
Stefano Marcantoni
Talk numberICTS:30892
Source RepositoryICTS-TIFR
Collection

Abstract

In this talk, I will consider a finite-level quantum system linearly coupled to a bosonic reservoir, that is the prototypical example of an open quantum system. I will present recent results on the reduced dynamics of the finite system when the coupling constant tends to infinity, i.e. in the ultrastrong coupling limit. In particular, I will show that the dynamics corresponds to a nonselective projective measurement followed by a unitary evolution with an effective (Zeno) Hamiltonian. I will also discuss the connection with the usual setting for the quantum Zeno effect, based on repeated measurements.
The rigorous proof of the limit is quite simple and can be generalized to the case of a small system interacting with two reservoirs when one of the couplings is finite and the other one tends to infinity. In this second scenario the reduced dynamics is richer and possibly non-Markovian.
Joint work with Marco Merkli, arXiv:2411.06817.