Pulse-regulated single-photon generation via quantum interference in a χ⁽²⁾ nonlinear nanocavity

Abstract

A scalable on-chip single-photon source at telecommunications wavelengths is an essential component of quantum communication networks. In this work, we numerically construct a pulse-regulated single-photon source based on an optical parametric amplifier in a nanocavity. Under the condition of pulsed excitation, we study the photon statistics of the source using the Monte Carlo wave-function method. The results show that there exits an optimum excitation pulse width for generating high-purity single photons, while the source brightness increases monotonically with increasing excitation pulse width. More importantly, our system can be operated resonantly and we show that in this case the oscillations in g (2) (0) is completely suppressed.

Photon blockade in a bi-mode nonlinear nano-cavity embedded with a quantum-dot

“…The proposed model can be considered a composite model of the J-C model and the bi-mode driven nonlinear optical cavity. Studies have indicated that CPB and UCPB exist in the Jaynes-Cummings (J-C) model with strong coupling and the bi-mode driven nonlinear optical cavity [17,18]. Thus, we expect CPB induced by strong nonlinear interaction and UCPB induced by quantum interference to simultaneously appear in the proposed model, when the system is in the strong coupling regime.…”

“…In addition, when g = 0, our scheme can be regarded as a bi-mode driven optical cavity, which has been studied in Ref. [18] in which the PB arises only from the quantum interference. As discussed below, we find the optimal condition of photon antibunching in terms of effective parametric gain and coupling strength based on the effective Hamiltonian H ef f , and analyze the difference between the features of the PB effect and the J-C model and the bi-mode driven optical cavity.…”

“…To differentiate the photon antibunching processes induced by different physical mechanisms, the antibunching induced by strong nonlinear interaction between photons is referred to as conventional photon blockade (CPB), whereas that by the quantum interference is termed unconventional photon blockade (UCPB). Since its proposition, many theoretical and experimental works have focused on UCPB in different systems, such as coupled nonlinear cavities[14], superconducting qubit microwave cavity [15] and opto-mechanical systems, two coupled nonlinear single-mode cavity system[16], and χ (2) nonlinear coupled or doubly-resonant cavity system [17,18].…”

“…To differentiate the photon antibunching processes induced by different physical mechanisms, the antibunching induced by strong nonlinear interaction between photons is referred to as conventional photon blockade (CPB), whereas that by the quantum interference is termed unconventional photon blockade (UCPB). Since its proposition, many theoretical and experimental works have focused on UCPB in different systems, such as coupled nonlinear cavities[14], superconducting qubit microwave cavity [15] and opto-mechanical systems, two coupled nonlinear single-mode cavity system[16], and χ (2) nonlinear coupled or doubly-resonant cavity system [17,18].Currently, studies have found that the quantum interference phenomenon can be used to enhance the CPB, and consequently the purity of the generated single-photon [19]. In addition, we note that CPB and UCPB can coexist in the same quantum optics system [19,20], which is helpful in further understanding the physical mechanism behind CPB/UCPB.In this study, we propose a model to generate strong PB with a single quantum-dot (QD) that is strongly coupled to a bi-mode nonlinear nanocavity, which is filled with χ (2) medium.…”

Enhanced photon blockade in an optomechanical system with parametric amplification

“…To achieve PB, researchers have proposed two different physical mechanisms, which respectively rely on the anharmonic eigenenergy spectrum [18][19][20] and the destructive quantum interference between excitation paths [21][22][23][24] and are so-called conventional and unconventional PB. Specifically, the anharmonic eigenenergy spectrum in the convention PB mechanism usually comes from kinds of nonlinearities.…”