Generation of single photons from an atom-cavity system

Abstract

A single rubidium atom trapped within a high-finesse optical cavity is an efficient source of single photons. We theoretically and experimentally study single-photon generation using a vacuum stimulated Raman adiabatic passage. We experimentally achieve photon generation efficiencies of up to 34% and 56% on the D1 and D2 line, respectively. Output coupling with 89% results in record-high efficiencies for single photons in one spatiotemporally well-defined propagating mode. We demonstrate that the observed generation efficiencies are constant in a wide range of applied pump laser powers and virtual level detunings. This allows for independent control over the frequency and wave packet envelope of the photons without loss in efficiency. In combination with the long trapping time of the atom in the cavity, our system constitutes a significant advancement toward an on-demand, highly efficient single-photon source for quantum information processing tasks.Comment: 7 pages, 5 figure

Advances in quantum control of three‐level superconducting circuit architectures

“…STIRAP is the basis of many protocols from preparation of superpositions to transfer of wavepackets , with still unexplored potentialities for quantum information and quantum control. Protocols with always‐on fields and their generalization to circuit‐QED architectures yield a key ingredient for several tasks involving individual microwave photons, from Fock state generation illustrated in this work, to single‐photon generation photon conversion and their interaction. The key point is that as conventional Λ‐STIRAP triggers fluorescence by the absorption of an ε 2 photon and the emission of an one, when classical fields are substituted by quantized mode of the electromagnetic field in a cavity, the generalized protocol implements photon absorption‐emission cycles, which are a building block for processing in circuit‐QED networks.…”

Efficient excitation of dye molecules for single photon generation

“…This is sometimes called a source of photons on demand. An isolated atom provides a particularly well defined quantum system [10,11], but the need for ultra-high vacuum and some sort of trap makes this difficult to scale up in practical devices. Consequently, there is great interest in solid-state alternatives [12] such as quantum dots [13][14][15][16], defects in diamond [17,18], impurities in other solids [19], and our system of choice-single organic molecules [20][21][22].…”

Heralded Storage of a Photonic Quantum Bit in a Single Atom

“…The storage efficiency is given by Rη det , where R is the reflectivity of the atom-cavity system on resonance. Our experiment exhibits an average R ¼ ð69 AE 2Þ% and achieves an efficiency of ð39 AE 4Þ%, which is a factor of 2R=ðη gen η det Þ, i.e., more than 4 times, higher than what can be achieved by using an optical BSM with state-of-the-art photon sources (η gen ¼ 0.6) [22] and the best commercially available single-photon detectors [η det ¼ 0.56ð5Þ at 780 nm]. Even with the unrealistic assumption of a perfect single-photon source (η gen ¼ 1) and perfect single-photon detectors (η det ¼ 1), employed both in our realization and in the optical BSM, we improve by a factor of 1.4, thereby outperforming any optical BSM.…”