Homodyne detection of coherence and phase shift of a quantum dot in a cavity

Bakker, Morten P.; Snijders, Henk; Löffler, W.; Barve, Ajit V.; Coldren, L.A.; Bouwmeester, Dirk; Exter, M. P. van

doi:10.1364/ol.40.003173

Cited by 14 publications

(6 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3b shows the emitted single photon rate measured simultaneously. For increasing laser power, we observe a saturation of the single-photon count rate at around 1 nW, which corresponds well to previous results on related devices [26]. Based on the bare lifetime of the QD (γ || = 1.0 ± 0.4 ns −1 ) one would expect that GHz rate single photons can be obtained, but we observe an increase of g 2 (0) for increasing laser power.…”

supporting

confidence: 90%

Fiber-Coupled Cavity-QED Source of Identical Single Photons

et al. 2018

View full text Add to dashboard Cite

We present a fully fiber-coupled source of high-fidelity single photons. An (In,Ga)As semiconductor quantum dot is embedded in an optical Fabry-Perot microcavity with a robust design and rigidly attached single-mode fibers, which enables through-fiber cross-polarized resonant laser excitation and photon extraction. Even without spectral filtering, we observe that the incident coherent light pulses are transformed into a stream of single photons with high purity (97%) and indistinguishability (90%), which is measured at an in-fiber brightness of 5% with an excellent cavity-mode-to-fiber coupling efficiency of 85%. Our results pave the way for fully fiber-integrated photonic quantum networks. Furthermore, our method is equally applicable to fiber-coupled solid-state cavity-QED-based photonic quantum gates. DOI: 10.1103/PhysRevApplied.9.031002 Every isolated two-level quantum system-for example, an atom, an ion, a color center, or a quantum dot-can, in principle, be turned into a bright single-photon source [1,2]. Ideally, such a source produces a stream of single photons, with never more or less than one photon per time bin, and with all having the same Fourier limited spectrum and timing. Such a source would be essential for the exploration of numerous quantum technologies, among them optical quantum computing [3-6] and simulation [7]. Furthermore, the reduced fluctuations of such single-photon light would enable exciting opportunities if noise is a limiting factor, in fields ranging from metrology to microscopy.However, only very recently have high-fidelity singlephoton sources been demonstrated [8][9][10][11][12][13] that simultaneously fulfill the key requirements: near-unity single-photon purity and indistinguishability of consecutively emitted photons, and high brightness. For a single-photon source, high brightness and on-demand availability is crucial for the efficient implementation of quantum photonic protocols. Additionally, to exploit the power of quantum interference, consecutively produced photons need to be indistinguishable, meaning that their wave functions must overlap well. Until recently, heralded spontaneous parametric down-conversion sources [14] were the state of the art for single-photon sources [15], with which most quantum communication and optical quantum computing protocols have been demonstrated [16]. The main problem with these sources is that the Poissonian statistics of the generated twin photons will always result in a trade-off between single-photon purity (the absence of N > 1 photon number states) and brightness (the probability of obtaining a photon per time slot).One way to deterministically produce single photons is to use trapped atoms [17], where single-photon rates up to around 100 kHz have recently been obtained [18]. In order to enable integration and an increase of the photon rate, solid-state systems have been investigated: of particular promise are semiconductor quantum dots (QDs) [1,19,20]. QDs have nanosecond-lifetime transitions that enable gigahertz-rate produc...

show abstract

supporting

confidence: 90%

Fiber-Coupled Cavity-QED Source of Identical Single Photons

et al. 2018

View full text Add to dashboard Cite

show abstract

“…To determine further system parameters, we model our QD cavity system by a two-polarization JC Hamiltonian coupled to the incident coherent field and take care of cavity and QD dissipation by the quantum master equation formalism3031. We compare experiment and theory for six different input–output polarizer settings to faithfully determine the model parameters, these measurements were performed for an input power of 100 pW to avoid saturation effects32. We obtain (see Supplementary Fig.…”

Section: Resultsmentioning

confidence: 99%

Purification of a single-photon nonlinearity

et al. 2016

View full text Add to dashboard Cite

Single photon nonlinearities based on a semiconductor quantum dot in an optical microcavity are a promising candidate for integrated optical quantum information processing nodes. In practice, however, the finite quantum dot lifetime and cavity-quantum dot coupling lead to reduced fidelity. Here we show that, with a nearly polarization degenerate microcavity in the weak coupling regime, polarization pre- and postselection can be used to restore high fidelity. The two orthogonally polarized transmission amplitudes interfere at the output polarizer; for special polarization angles, which depend only on the device cooperativity, this enables cancellation of light that did not interact with the quantum dot. With this, we can transform incident coherent light into a stream of strongly correlated photons with a second-order correlation value up to 40, larger than previous experimental results, even in the strong-coupling regime. This purification technique might also be useful to improve the fidelity of quantum dot based logic gates.

show abstract

“… 77 . Furthermore, for the reliable quantum information processing, researches have improved the capability of detection from the increase of the absorption 78 , 79 , and proposed the method of utilizing the positive-operator-value measurement elements 5 , 62 for the reliable implementation of PNR measurement.…”

Section: Discussionmentioning

confidence: 99%

Preparation of quantum information encoded on three-photon decoherence-free states via cross-Kerr nonlinearities

Heo

Kang

Hong³

et al. 2018

Sci Rep

View full text Add to dashboard Cite

We present a scheme to encode quantum information (single logical qubit information) into three-photon decoherence-free states, which can conserve quantum information from collective decoherence, via nonlinearly optical gates (using cross-Kerr nonlinearities: XKNLs) and linearly optical devices. For the preparation of the decoherence-free state, the nonlinearly optical gates (multi-photon gates) consist of weak XKNLs, quantum bus (qubus) beams, and photon-number-resolving (PNR) measurement. Then, by using a linearly optical device, quantum information can be encoded on three-photon decoherence-free state prepared. Subsequently, by our analysis, we show that the nonlinearly optical gates using XKNLs, qubus beams, and PNR measurement are robust against the decoherence effect (photon loss and dephasing) in optical fibers. Consequently, our scheme can be experimentally implemented to efficiently generate three-photon decoherence-free state encoded quantum information, in practice.

show abstract

Homodyne detection of coherence and phase shift of a quantum dot in a cavity

Cited by 14 publications

References 29 publications

Fiber-Coupled Cavity-QED Source of Identical Single Photons

Fiber-Coupled Cavity-QED Source of Identical Single Photons

Purification of a single-photon nonlinearity

Preparation of quantum information encoded on three-photon decoherence-free states via cross-Kerr nonlinearities

Contact Info

Product

Resources

About