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arXiv · 1604.06478

General Theory of Spontaneous Emission Near Exceptional Points

Adi Pick·Bo Zhen·Owen D. Miller·Chia W. Hsu·Felipe Hernandez·Alejandro W. Rodriguez·Marin Soljacic·Steven G. Johnson
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Abstract

We present a general theory of spontaneous emission at exceptional points (EPs)---exotic degeneracies in non-Hermitian systems. Our theory extends beyond spontaneous emission to any light--matter interaction described by the local density of states (e.g., absorption, thermal emission, and nonlinear frequency conversion). Whereas traditional spontaneous-emission theories imply infinite enhancement factors at EPs, we derive finite bounds on the enhancement, proving maximum enhancement of 4 in passive systems with second-order EPs and significantly larger enhancements (exceeding $400\times$) in gain-aided and higher-order EP systems. In contrast to non-degenerate resonances, EPs are associated with non-Lorentzian emission curves, leading to enhancements that scale polynomially with the resonance quality factor.

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Adi Pick, Bo Zhen, Owen D. Miller, Chia W. Hsu, Felipe Hernandez, Alejandro W. Rodriguez, Marin Soljacic, Steven G. Johnson. 2017-05-18. General Theory of Spontaneous Emission Near Exceptional Points. https://doi.org/10.1364/oe.25.012325

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