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Coherent generation of photonic fractional quantum Hall states in a cavity and the search for anyonic quasiparticles

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 نشر من قبل Shovan Dutta
 تاريخ النشر 2017
  مجال البحث فيزياء
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We present and analyze a protocol in which polaritons in a noncoplanar optical cavity form fractional quantum Hall states. We model the formation of these states and present techniques for subsequently creating anyons and measuring their fractional exchange statistics. In this protocol, we use a rapid adiabatic passage scheme to sequentially add polaritons to the system, such that the system is coherently driven from $n$- to $(n+1)$-particle Laughlin states. Quasiholes are created by slowly moving local pinning potentials in from outside the cloud. They are braided by dragging the pinning centers around one another, and the resulting phases are measured interferometrically. The most technically challenging issue with implementing our procedure is that maintaining adiabaticity and coherence requires that the two-particle interaction energy $V_0$ be sufficiently large compared to the single-polariton decay rate $gamma$, $V_0 /gamma gg 10 N^2 ln N$, where $N$ is the number of particles in the target state. While this condition is very demanding for present-day experiments where $V_0 /gammasim 50$, our protocol presents a significant advance over the existing protocols in the literature.



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