Photonic Structures with Topological Robustness: from Classical to Quantum

By Mohammad Hafezi

Electrical and Computer Engineering, University of Maryland, College Park, MD

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One of the promising applications of quantum computers is quantum simulation --- the ability to simulate quantum dynamics on an engineerable physical system. Such simulators allow us to investigate models that are practically impossible to study on a classical computer. For example, there are tremendous efforts underway to better understand systems with topological order --- global properties that are not discernible locally. The best known examples are quantum Hall effects in electronic system, where insensitivity to local properties manifests itself as conductance through edge states that is insensitive to defects and disorder.

In this talk, I demonstrate how similar physics can be observed for photons; specifically, how various quantum Hall Hamiltonians can be simulated in an optical platform. I report on the first observation of topological photonic edge state using silicon-on-insulator technology and our recent advance in studying quantum transport of such topological photonic structures. Furthermore, the addition of optical nonlinearity to this system provides a platform to implement fractional quantum Hall states of photons and anyonic states that have not yet been observed. More generally, the application of these ideas can lead to development of optical devices with topological protection for classical and quantum information processing.


Mohammad Hafezi Mohammad Hafezi is an Assistant Professor of Electrical and Computer Engineering at the University of Maryland (UMD), and a fellow at the Joint Quantum Institute (NIST-UMD) and IREAP. He received his diploma from Ecole Polytechnique, France, in 2003. After obtaining his Ph.D. from the Physics department at Harvard University, he moved to the Joint Quantum Institute as a postdoc in 2009. His research is at the interface of theoretical and experimental quantum optics and condensed-matter physics with a focus on fundamental physics and applications in quantum information science, precision measurement, and integrated photonics. His recent awards include the Sloan Research Fellowship and the Young Investor award of the Office of Naval Research.

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  • Mohammad Hafezi (2017), "Photonic Structures with Topological Robustness: from Classical to Quantum,"

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