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arXiv · 1508.02113

Tachyonic Dispersion in Coherent Networks

Y. D. Chong·Mikael C. Rechtsman
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Abstract

We propose a technique to realize a tachyonic band structure in a coherent network, such as an array of coupled ring resonators. This is achieved by adding "PT symmetric" spatially-balanced gain and loss to each node of the network. In a square-lattice network, the quasi-energy bandstructure exhibits a tachyonic dispersion relation, centered at either the center or corner of the Brillouin zone. There is one tachyonic hyperboloid in each gap, unlike in PT-symmetric tight-binding honeycomb lattices where the hyperboloids occur in pairs. The dispersion relation can be probed by measuring the peaks in transmission across a finite network as the gain/loss parameter is varied.

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Y. D. Chong, Mikael C. Rechtsman. 2015-08-10. Tachyonic Dispersion in Coherent Networks. https://doi.org/10.1088/2040-8978%2F18%2F1%2F014001

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