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arXiv · 1608.07003

Simultaneous Realization of Coherent Perfect Absorber and Laser by Zero-Index Media with both Gain and Loss

Ping Bai·Kun Ding·Gang Wang·Jie Luo·Zhao-Qing Zhang·C. T. Chan·Ying Wu·Yun Lai
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Abstract

We investigate a unique type of zero-index medium with both gain and loss (ZIMGL), whose effective permittivity and permeability are purely imaginary and of opposite signs. We show analytically that, by using a slab of ZIM-GL with equal magnitude of loss and gain, coherent perfect absorber (CPA) and laser, i.e. the socalled CPA-laser, can be achieved simultaneously. CPA-laser has been found previously in parity-time (PT) symmetric systems. However, the underlying physics in a PT-symmetric system is distinct from that in a ZIM-GL. By designing a photonic crystal (PC) composed of core-shell rods, with loss and gain distributed in either the core or the shell, we have realized such a ZIM-GL. The CPA-laser functionality of such a PC is also confirmed in our numerical simulations. Our work provides a different approach for simultaneous realization of CPA and laser besides PTsymmetric systems.

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Ping Bai, Kun Ding, Gang Wang, Jie Luo, Zhao-Qing Zhang, C. T. Chan, Ying Wu, Yun Lai. 2016-08-25. Simultaneous Realization of Coherent Perfect Absorber and Laser by Zero-Index Media with both Gain and Loss. https://doi.org/10.1103/physreva.94.063841

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