Colloquium: Physics & Astronomy – Dr. Hamidreza Ramezani
About the event
The Department of Physics and Astronomy invites all to a colloquium featuring faculty candidate, Dr. Hamidreza Ramezani. Dr. Hamidreza Ramezani will present their talk, “Exploiting wave transport in classical and quantum open systems.”
Meet for refreshments before the lecture at 3:45 – 4:10 p.m. in the foyer on floor G above the lecture hall.
Technological advancement, which have provided many new possibilities for better living for humankind, they also indicate that our needs have extended to new dimensions. This shift has encouraged us to find innovative approaches and utilize every possible degree of freedom to propose elegant mechanisms that bring us full control over wave transport in linear, and nonlinear classical and quantum system.
In this talk, I specifically focus on symmetries that require the system to be open or symmetries that can be implemented using asymmetric channels. The existence of such symmetries drives us to investigate non-Hermitian Hamiltonians. Non-Hermitian Hamiltonians are achievable by means of synthesizing wave-matter-interaction and can be implemented in non-Hermitian electronic, acoustic and optical systems. I will show how exploiting symmetries like parity and time symmetry and the resulting intrinsic topological properties of such symmetric systems reveal exquisite and unprecedented functionalities that are not observed in nature. Specifically, I will discuss the effects that have gotten the most attention in the field of non-Hermitian systems and significantly affect the growth of the field. In particular, I show how tailoring “meta-potentials” can lead to nonlinear-assisted asymmetric light propagation [1], unidirectional invisibility [2], unidirectional lasing [3], nonreciprocal localization of photons [4], tunable flat bands [5] and ultra-fast low-cost quantum state transfer [6]. Toward the end of the talk, I will discuss the future directions of synthetic wave transport in quantum field theory, topological systems, and directed energy which reveal the significant impact of meta-engineering of wave transport on science and technology.
[1] H. Ramezani, T. Kottos, R. El-Ganainy, D. Christodoulides, PRA, 82 (4), 043803 (2010), N. Shitrit, J. Kim, D. Barth, H. Ramezani, Y. Wang, X. Zhang, PRL, 121 (4), 046101(2018) [2] Z. Lin, H. Ramezani, T. Eichelkraut, T. Kottos, H. Cao, D. Christodoulides, PRL 106 (21), 213901 (2011) [3] H. Ramezani, H. K. Li, Y. Wang, X. Zhang, PRL 113 (26), 263905 (2014), H. Ramezani, S. Kalish, I. Vitebskiy, T. Kottos PRL, 112 (4), 043904 (2014) [4] H. Ramezani, P. Jha, Y. Wang, X. Zhang, PRL, 120 (4), 043901(2018) [5] H. Ramezani, 96 (1), 011802 (2017) [6] F. Mostafavi, L. Yuan, H. Ramezani, PRL, 122, 050404 (2019)