Physics Special Seminar with Federico Roccati on Quantum optics in (non-)Hermitian topological photonic reservoirs

Topology and quantum optics are two fields whose interplay can give rise to new physics [1]. By properly designing a photonic lattice (i.e., the structured reservoir), it is possible to engineer photon-mediated spin Hamiltonians between quantum emitters coupled to it. In
particular, it is possible to endow photonic structures with Hermitian or non-Hermitian topological properties, the latter being typical of dissipative lattices [2]. In my talk, I will cover the recent advancements in the field, the current experimental implementations of such setups, and our recent results. Specifically, I will describe how, engineering dissipation (i.e., non-Hermiticity) in a photonic lattice, exotic interactions can be mediated between quantum emitters, unachievable in the Hermitian case [3]. Finally, I will illustrate the topological correspondence that exists between the topology of a photonic lattice and the topology of the photon-mediated interactions [4].

[1] M. Bello, G. Platero, J. I. Cirac, A. González-Tudela. Sci. Adv. 5,
eaaw0297 (2019).
[2] T. Ozawa et al. Rev. Mod. Phys. 91, 015006 (2019).
[3] F. Roccati, S. Lorenzo, G. Calajò, G. M. Palma, A. Carollo, F.
Ciccarello. Optica 9, 565-571 (2022).
[4] F. Roccati, M. Bello, Z. Gong, M. Ueda, F. Ciccarello, A. Chenu, A.
Carollo. Nat Commun 15, 2400 (2024).

This lecture was made possible by the William C. Ferguson fund.