A stand-alone fiber-coupled single-photon source

Abstract

In this work, we present a stand-alone and fiber-coupled quantum-light source. The plug-and-play device is based on an optically driven quantum dot delivering single photons via an optical fiber. The quantum dot is deterministically integrated in a monolithic microlens which is precisely coupled to the core of an optical fiber via active optical alignment and epoxide adhesive bonding. The rigidly coupled fiber-emitter assembly is integrated in a compact Stirling cryocooler with a base temperature of 35 K. We benchmark our practical quantum device via photon auto-correlation measurements revealing g(2)(0) = 0.07 ± 0.05 under continuous-wave excitation and we demonstrate triggered non-classical light at a repetition rate of 80 MHz. The long-term stability of our quantum light source is evaluated by endurance tests showing that the fiber-coupled quantum dot emission is stable within 4% over several successive cool-down/warm-up cycles. Additionally, we demonstrate non-classical photon emission for a user-intervention-free 100-hour test run and stable single-photon count rates up to 11.7 kHz with a standard deviation of 4%.

Electronic states of (InGa)(AsSb)/GaAs/GaP quantum dots

“…By taking the basis of two (six) ground state electron and two (six) hole states for calculations without (with) the effects of correlation, we have found the effect on FSS and ∆E bd energies to be ∼ 2 µeV (not shown). In total, the above findings make In 1−x Ga x As y Sb 1−y QDs with GaAs IL on GaP substrate a promising candidate for realization of optically bright single photon sources, different to type-I (In,Ga)As/GaAs QDs which are currently being under investigation as sources of light for quantum cryptography applications [80,85,86].…”

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

“…a (0) becomes infinite) in addition to the previously reported perfect antibunching (g (2) a (0) = 0). More particularly, we focus on the effect of two important aspects not considered previously: the impact of dephasing, since this is a detrimental ingredient that is typically present, especially in a solid-state platform, and the role of detuning from the two-level system, from either the driving laser and/or the detector.…”

“…Similar schemes have been recently implemented to obtain a source of indistinguishable photons [14], to observe the rising of the socalled dynamical Mollow triplet [67] and to unveil the photon correlations of the light emitted by a Jaynes-Cummings system [68]. In our case, we find that not only this laser-correction allows to realise simultaneously subnatural linewidth spectral emission and antibunching, but also that it produces a stronger type of single-photon emission with a plateau in the time-resolved photon correlation g (2) a (τ ). Such sources therefore provide a new playground of their own, whose properties, advantages over existing sources and further possibilities deserve an immediate attention, as we wait for their experimental implementation.…”

“…(1) and then taking the limit g → 0, which allows the dynamics of the two-level system to be independent from that of the sensor. The bandwidth of the sensor is given by its decay rate Γ and is included as an extra term (Γ/2)L a ρ in the master equation (2). For quantities such as populations, which would vanish with g → 0, one should use instead the more complete but also heavier cascaded formalism, which we have shown is equivalent to the more lightweight sensor method as far as correlations are concerned [71].…”

Photon-antibunching in the fluorescence of statistical ensembles of emitters at an optical nanofiber-tip

“…An ideal source emits exactly one photon into a single optical mode at an arbitrarily chosen time, with each photon being indistinguishable from all others generated by the source. The demand that no more than a single photon is emitted at a time typically requires the use of single emitters, for instance single atoms, molecules, quantum dots, or single defects in crystal lattices [2][3][4][5][6][7][8][9][10]. The fabrication of such single emitter sources is however technically demanding [11], which motivates the search for new approaches that are simpler to build.…”