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Non-reciprocal and robust photonics with opto-mechanical systems

February 24, 2020 - 11:00am
Gaurav Bahl

Time-reversal symmetry is a defining property for wave phenomena in linear stationary media. However, broken time-reversal symmetry is required for producing essential nonreciprocal devices like isolators, circulators, and gyrators. Magneto-optic methods can enable nonreciprocal behavior for electromagnetic waves, but this approach does not readily translate to the microscale or for atomic-PNT technologies, compelling us to search for nonmagnetic solutions. This talk will describe our work to exploit light-sound interactions for producing strongly nonreciprocal behavior in chip-scale systems. The optomechanical physics within these devices enable fundamental experiments having analogies to quantum condensed matter phenomena, including phonon laser action, cooling, and electromagnetically induced transparency [1,2]. We demonstrate how mechanics is uniquely positioned to solve long standing challenges for photonic integrated circuits that are required for cold-atom microsystems and related quantum technologies [3]. Moreover, the underlying nonreciprocal behavior enables robust photonic devices that are immune to backscattering induced by material defects and disorder [4,5]. Time permitting, I will introduce our work on how a synthetic Hall effect can be leveraged to produce strongly nonreciprocal metamaterials [6], and some of our research efforts on robust topological pumping [7] and high-order topological insulators [8].



  1. G. Bahl et al, Nature Physics 8(3), pp. 203-207, 2012.

  2. J. Kim et al, Nature Physics 11, pp. 275-280, 2015.

  3. D. Sohn et al, Nature Photonics 12, 91-95, 2018.

  4. S. Kim et al, Nature Communications 8, 205, 2017.

  5. S. Kim et al, Optica 6(8), pp.1016-1022, 2019.

  6. C.W. Peterson et al, Science Advances 4(6), eaat0232, 2018.

  7. I. Grinberg et al, Nature Communications (preprint on arXiv :1905.02778), 2020.

  8. C.W. Peterson et al, Nature 555, pp.346–350, 2018.

Host: Mohammad Hafezi

ATL 2400