This Demonstration shows the two-photon statistics as defined by Glauber's intensity correlator for the light emitted by an optical emitter coupled (with strength ) to a single-mode cavity. If the emitter is modeled as a weakly anharmonic oscillator, this models microcavity polaritons. If the strength of the nonlinearity goes to infinity, this recovers the Jaynes–Cummings model where the emitter is a two-level system. In both cases, a blockade effect arises when the photon statistics of a driving laser exciting the system is strongly affected by it. This is shown for coherent driving of both the cavity and the emitter (with ratio χ, 0 for cavity pumping only and 1 for emitter pumping only, with a phase difference ) in the space of cavity-emitter detuning (horizontal axis) and laser-emitter detuning (vertical axis), in units of the coupling strength. Blue corresponds to A, antibunching, that is, or suppression of photon coincidences; red to B, bunching, that is, or photon bursts; and white to uncorrelated photons. Theory shows how these features arise from conventional C and unconventional U mechanisms for both types of statistics, leading to four types of features: UA, CA, UB and CB. The Jaynes–Cummings blockade is recovered for already (the emitter emission goes to zero everywhere as ).
Snapshot 1: polariton blockade with large interactions of the emitter recovers the Jaynes–Cumming limit
Snapshot 2: the underlying resonances, UA (unconventional antibunching) in dashed blue, CA (conventional antibunching) in solid blue, UB (unconventional bunching) in dashed red and CB (conventional bunching) in solid red
Snapshot 3: the polariton blockade in today samples corresponds to a case of very weak interactions, with closely packed features
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