Impact of detuning and dephasing on a laser-corrected subnatural-linewidth single-photon source

Abstract

The elastic scattering peak of a resonantly driven two-level system has been argued to provide narrow-linewidth antibunched photons. Although independent measurements of spectral width on the one hand and antibunching on the other hand do seem to show that this is the case, a joint measurement reveals that only one or the other of these attributes can be realised in the direct emission. We discuss a scheme which interferes the emission with a laser to produce simultaneously single photons of subnatural linewidth. In particular, we consider the effect of dephasing and of the detuning between the driving laser and/or the detector with the emitter. We find that also in presence of dephasing, our scheme brings considerable improvement as compared to the standard scheme. arXiv:1806.08774v2 [quant-ph]

Conventional and Unconventional Photon Statistics

“…It can in fact be also optimized (i.e., reduced) like all types of UA and as a result, should even reach to lowest order for a proper choice of the detuning, that will depend on N in a way that remains to be computed. Since we have shown, however, that the interference nature of UA makes it sensitive to dephasing, and that detuning [ 132 ] results in fast oscillations in autocorrelation times, with a narrowing plateau of antibunching, one can also expect this antibunching to be particularly fragile and difficult to resolve when including a realistic model for its detection. This is consistent with the finding of ref.…”

“…The simplest way to account for such an effect is to include to the master equation a term in the Lindblad form which describes pure dephasing at a rate . [ 131 ] Either from exact analytical results that can be obtained in some cases, such as for the two‐level system, [ 132 ] or from numerical simulations, it happens that, as a rule, unconventional features are fragile to dephasing, in the sense that resonances producing either bunching or antibunching, but most particularly those of strong antibunching that cancel exactly to first‐order in the driving, are quickly spoiled by small values of dephasing. In contrast, conventional features are robust and the loss of antibunching becomes significant only when pure dephasing is a sizable fraction of radiative lifetimes.…”

Asymmetric coupling between two quantum emitters

“…As such, one may use cascaded theory to posit a well-defined criterion for chiral coupling [28,36,40]. Meanwhile, a number of papers have appeared recently successfully employing the cascaded formalism to uncover nontrivial photon correlations [41][42][43][44].…”

Asymmetric coupling between two quantum emitters

“…One notices that dissipative coupling γ only leads to frequency shifts ω p if the coherent couping g is nonzero, while the coherent coupling g only modifies the collective damping rates γ p if the dissipative couping γ is nonzero, due to the form of Eq. (41). Furthermore, the complex frequency of Eq.…”

“…As such, one may use cascaded theory to posit a well-defined criterion for chiral coupling [26,33]. Meanwhile, a number of papers have appeared recently successfully employing the cascaded formalism to uncover nontrivial photon correlations [37][38][39][40][41].…”