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arXiv · 1205.2176

Experimental observation of the dual behavior of ${\cal PT}$-symmetric scattering

Zin Lin·Joseph Schindler·Fred M. Ellis·Tsampikos Kottos
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Abstract

We investigate experimentally parity-time (${\cal PT}$) symmetric scattering using $LRC$ circuits in an inductively coupled ${\cal PT}$- symmetric pair connected to transmission line leads. In the single-lead case, the ${\cal PT}$-symmetric circuit acts as a simple dual device - an amplifier or an absorber depending on the orientation of the lead. When a second lead is attached, the system exhibits unidirectional transparency for some characteristic frequencies. This non-reciprocal behavior is a consequence of generalized (non-unitary) conservation relations satisfied by the scattering matrix.

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Zin Lin, Joseph Schindler, Fred M. Ellis, Tsampikos Kottos. 2012-05-10. Experimental observation of the dual behavior of ${\cal PT}$-symmetric scattering. https://doi.org/10.1103/physreva.85.050101

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