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arXiv · 2004.01362

Observation of two PT transitions in an electric circuit with balanced gain and loss

Tishuo Wang·Jianxiong Fang·Zhongyi Xie·Nenghao Dong·Yogesh N Joglekar·Zixin Wang·Jiaming Li·Le Luo
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Abstract

We investigate PT -symmetry breaking transitions in a dimer comprising two LC oscillators, one with loss and the second with gain. The electric energy of this four-mode model oscillates between the two LC circuits, and between capacitive and inductive energy within each LC circuit. Its dynamics are described by a non-Hermitian, PT -symmetric Hamiltonian with three different phases separated by two exceptional points. We systematically measure the eigenfrequencies of energy dynamics across the three regions as a function of gain-loss strength. In addition to observe the well-studied PT transition for oscillations across the two LC circuits, at higher gain-loss strength, transition within each LC circuit is also observed. With their extraordinary tuning ability, PT -symmetric electronics are ideally suited for classical simulations of non-Hermitian systems

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Tishuo Wang, Jianxiong Fang, Zhongyi Xie, Nenghao Dong, Yogesh N Joglekar, Zixin Wang, Jiaming Li, Le Luo. 2020-04-03. Observation of two PT transitions in an electric circuit with balanced gain and loss. https://doi.org/10.1140/epjd%2Fe2020-10131-7

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