528 research outputs found
Coherent storage of temporally multimode light using a spin-wave atomic frequency comb memory
No full textWe report on the coherent and multi-temporal mode storage of light using the full atomic frequency comb memory scheme. The scheme involves the transfer of optical atomic excitations in Pr3+:Y2SiO5 to spin waves in hyperfine levels using strong single-frequency transfer pulses. Using this scheme, a total of five temporal modes are stored and recalled on-demand from the memory. The coherence of the storage and retrieval is characterized using a time-bin interference measurement resulting in visibilities higher than 80%, independent of the storage time. This coherent and multimode spin-wave memory is promising as a quantum memory for light.</p
In situ characterization of an optically thick atom-filled cavity
No full text A means for precise experimental characterization of the dielectric susceptibility of an atomic gas inside an optical cavity is important for the design and operation of quantum light-matter interfaces, particularly in the context of quantum information processing. Here we present a numerically optimized theoretical model to predict the spectral response of an atom-filled cavity, accounting for both homogeneous and inhomogeneous broadening at high optical densities. We investigate the regime where the two broadening mechanisms are of similar magnitude, which makes the use of common approximations invalid. Our model agrees with an experimental implementation with warm caesium vapor in a ring cavity. From the cavity response, we are able to extract important experimental parameters, for instance the ground-state populations, total number density, and the magnitudes of both homogeneous and inhomogeneous broadening. </p
Preparing narrow velocity distributions for quantum memories in room-temperature alkali-metal vapors
No full textQuantum memories are a crucial technology for enabling large-scale quantum networks through synchronization of probabilistic operations. Such networks impose strict requirements on quantum memory, such as storage time, retrieval efficiency, bandwidth, and scalability. On- and off-resonant ladder protocols on warm atomic vapor platforms are promising candidates, combining efficient high-bandwidth operation with low-noise on-demand retrieval. However, their storage time is severely limited by motion-induced dephasing caused by the broad velocity distribution of atoms composing the vapor. In this paper, we demonstrate velocity selective optical pumping to overcome this decoherence mechanism. This will increase the achievable memory storage time of vapor memories. This technique can also be used for preparing arbitrarily shaped absorption profiles, for instance, preparing an atomic frequency comb absorption feature
Experimental realization of light with time-separated correlations by rephasing amplified spontaneous emission
No full textAmplified spontaneous emission is a common noise source in active optical systems, it is generally seen as being an incoherent process. Here we excite an ensemble of rare earth ion dopants in a solid with a π pulse, resulting in amplified spontaneous emission. The application of a second π pulse leads to a coherent echo of the amplified spontaneous emission that is correlated in both amplitude and phase. For small optical thicknesses, we see evidence that the amplified spontaneous emission and its echo are entangled.</p
Coherent optical ultrasound detection with rare-earth ion dopants
No full textWe describe theoretical and experimental demonstration for optical detection of ultrasound using a spectral hole engraved in cryogenically cooled rare-earth ion-doped solids. Our method utilizes the dispersion effects due to the spectral hole to perform phase-to-amplitude modulation conversion. Like previous approaches using spectral holes, it has the advantage of detection with large étendue. The method also has the benefit that high sensitivity can be obtained with moderate absorption contrast for the spectral holes.</p
Ultrasound detection using dispersion due to spectral holes
No full textDetection of ultrasound requires high efficiency phase to amplitude conversion. We demonstrate detection using dispersive effects in hole-burning materials which have large étendue compared to conventional methods. We show high sensitivity using modest hole parameters.</p
A solid state spin-wave quantum memory for photonic time-Bin qubits
No full textRare-earth (RE) doped crystals are promising candidates as quantum memories as they offer coherence properties comparable to those of atomic systems, but free of the drawbacks deriving from the atomic motion. The research on RE doped crystals quantum memories has been so far mostly focused on the mapping of quantum bits to optical collective excitations using the atomic frequency comb (AFC) or the gradient echo memory protocols [1-3]. However, this leads to short lived and mostly pre-determined storage. In this contribution, we report the first solid state spin-wave optical quantum memory with on-demand read-out. We also demonstrate the first spin-wave storage of time-bin qubits with conditional fidelities higher than for classical memories [4]
sj-docx-1-jtr-10.1177_00472875231217735 – Supplemental material for Operationalizing Transformative Tourism: Creating Dementia-Friendly Outdoor and Nature-Based Visitor Experiences
No full textSupplemental material, sj-docx-1-jtr-10.1177_00472875231217735 for Operationalizing Transformative Tourism: Creating Dementia-Friendly Outdoor and Nature-Based Visitor Experiences by Stephen J. Page, Joanne Connell, Stephan Price, Steven Owen, Katie Ledingham and Linda Clare in Journal of Travel Research</p
A Single-Photon-compatible Telecom-C-Band Quantum Memory in a Hot Atomic Gas
No full textThe efficient storage and on-demand retrieval of quantum optical states that
are compatible with the telecommunications C-band is a requirement for future
terrestrial-based quantum optical networking. Spectrum in the C-band minimises
optical fiber-propagation losses, and broad optical bandwidth facilitates
high-speed networking protocols. Here we report on a telecommunication
wavelength and bandwidth compatible quantum memory. Using the Off-Resonant
Cascaded Absorption protocol in hot Rb vapour, we demonstrate a total
memory efficiency of with a Doppler-limited storage time of
ns. We characterise the memory performance with weak coherent
states, demonstrating signal-to-noise ratios greater than unity for mean photon
number inputs above per pulse
sj-docx-2-jtr-10.1177_00472875231217735 – Supplemental material for Operationalizing Transformative Tourism: Creating Dementia-Friendly Outdoor and Nature-Based Visitor Experiences
No full textSupplemental material, sj-docx-2-jtr-10.1177_00472875231217735 for Operationalizing Transformative Tourism: Creating Dementia-Friendly Outdoor and Nature-Based Visitor Experiences by Stephen J. Page, Joanne Connell, Stephan Price, Steven Owen, Katie Ledingham and Linda Clare in Journal of Travel Research</p
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