Emergence of microfrequency comb via limit cycles in dissipatively coupled condensates
Abstract
Self-sustained oscillations, limit cycles, are a fundamental phenomenon unique to nonlinear dynamic systems of high-dimensional phase space. They enable understanding of a wide range of cyclic processes in natural, social and engineering systems. Here we show that limit cycles form in coupled polariton cavities following the breaking of Josephson coupling, leading to frequency-comb emission. The limit cycles and destruction of Josephson coupling both appear due to interplay between strong polariton-polariton interaction and a dissipative contribution to the cavity coupling. The resulting nonlinear dynamics of the condensates is characterized by asymmetric population distribution and nontrivial average phase difference between the two condensates, and by time-periodic modulation of their amplitudes and phases. The latter is manifested by coherent emission of new equidistant frequency components. The emission spectrum resembles that of a micro-frequency comb, but originates from a fundamentally different mechanism than that of existing frequency combs. It allows non-resonant excitation with a power input much below the conventional semiconductor laser threshold. The comb line spacing is determined by the interaction and coupling strengths, and is adjustable up to multi-terahertz frequency. The work establishes coupled polariton cavities as an experimental platform for rich nonlinear dynamic phenomena.
Citation
Kim , S , Rubo , Y G , Liew , T C H , Brodbeck , S , Schneider , C , Höfling , S & Deng , H 2020 , ' Emergence of microfrequency comb via limit cycles in dissipatively coupled condensates ' , Physical Review. B, Condensed matter and materials physics , vol. 101 , no. 8 , 085302 . https://doi.org/10.1103/PhysRevB.101.085302
Publication
Physical Review. B, Condensed matter and materials physics
Status
Peer reviewed
ISSN
1098-0121Type
Journal article
Rights
Copyright © 2020 American Physical Society. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1103/PhysRevB.101.085302
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