01932nas a2200181 4500008004100000245005700041210005700098260001300155520138000168100002501548700002001573700002201593700002701615700002301642700002501665700002301690856003701713 2020 eng d00aCritical Theory for the Breakdown of Photon Blockade0 aCritical Theory for the Breakdown of Photon Blockade c6/9/20203 a
Photon blockade is the result of the interplay between the quantized nature of light and strong optical nonlinearities, whereby strong photon-photon repulsion prevents a quantum optical system from absorbing multiple photons. We theoretically study a single atom coupled to the light field, described by the resonantly driven Jaynes--Cummings model, in which case the photon blockade breaks down in a second order phase transition at a critical drive strength. We show that this transition is associated to the spontaneous breaking of an anti-unitary PT-symmetry. Within a semiclassical approximation we calculate the expectation values of observables in the steady state. We then move beyond the semiclassical approximation and approach the critical point from the disordered (blockaded) phase by reducing the Lindblad quantum master equation to a classical rate equation that we solve. The width of the steady-state distribution in Fock space is found to diverge as we approach the critical point with a simple power-law, allowing us to calculate the critical scaling of steady state observables without invoking mean-field theory. We propose a simple physical toy model for biased diffusion in the space of occupation numbers, which captures the universal properties of the steady state. We list several experimental platforms where this phenomenon may be observed.
1 aCurtis, Jonathan, B.1 aBoettcher, Igor1 aYoung, Jeremy, T.1 aMaghrebi, Mohammad, F.1 aCarmichael, Howard1 aGorshkov, Alexey, V.1 aFoss-Feig, Michael uhttps://arxiv.org/abs/2006.05593