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arXiv · 1708.05883

Normal--mode splitting in a weakly coupled optomechanical system

Massimiliano Rossi·Nenad Kralj·Stefano Zippilli·Riccardo Natali·Antonio Borrielli·Gregory Pandraud·Enrico Serra·Giovanni Di Giuseppe·David Vitali
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Abstract

Normal--mode splitting is the most evident signature of strong coupling between two interacting subsystems. It occurs when two subsystems exchange energy between themselves faster than they dissipate it to the environment. Here we experimentally show that a weakly coupled optomechanical system at room temperature can manifest normal--mode splitting when the pump field fluctuations are anti-squashed by a phase-sensitive feedback loop operating close to its instability threshold. Under these conditions the optical cavity exhibits an effectively reduced decay rate, so that the system is effectively promoted to the strong coupling regime.

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Massimiliano Rossi, Nenad Kralj, Stefano Zippilli, Riccardo Natali, Antonio Borrielli, Gregory Pandraud, Enrico Serra, Giovanni Di Giuseppe, David Vitali. 2017-08-19. Normal--mode splitting in a weakly coupled optomechanical system. https://doi.org/10.1103/physrevlett.120.073601

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