Quantum Communication Using Semiconductor Quantum Dots

Advanced Quantum Technologies, Journal Year: 2022, Volume and Issue: 5(7)

Published: April 15, 2022

Abstract Worldwide, enormous efforts are directed toward the development of so‐called quantum internet. Turning this long‐sought‐after dream into reality is a great challenge that will require breakthroughs in communication and computing. To establish global, quantum‐secured infrastructure, photonic technologies doubtlessly play major role, by providing interfacing essential resources, for example, flying‐ stationary qubits or memories. Over last decade, significant progress has been made engineering on‐demand light sources based on semiconductor dots, which enable generation close‐to‐ideal single‐ entangled‐photon states, useful applications information processing. This review focuses implementations of, building blocks for, using quantum‐light epitaxial dots. After reviewing main notions introducing devices used single‐photon generation, an overview experimental key distribution protocols dot provided. Furthermore, recent networks as well thereof summarized. The article closes with outlook, discussing future perspectives field identifying challenges to be solved.

Language: Английский

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Quantum dots for photonic quantum information technology

Advances in Optics and Photonics, Journal Year: 2023, Volume and Issue: 15(3), P. 613 - 613

Published: July 10, 2023

The generation, manipulation, storage, and detection of single photons play a central role in emerging photonic quantum information technology. Individual serve as flying qubits transmit the at high speed with low losses, for example between individual nodes networks. Due to laws mechanics, communication is fundamentally tap-proof, which explains enormous interest this modern On other hand, stationary or states computers can potentially lead increases performance through parallel data processing, outperform classical specific tasks when advantage achieved. Here, we discuss depth great potential dots (QDs) In context, QDs form key resource implementation networks because they generate on-demand. Moreover, are compatible mature semiconductor technology, so that be integrated comparatively easily into nanophotonic structures, basis light sources circuits. After thematic introduction, present numerical methods theoretical approaches device design physical description dot devices. We then technical solutions epitaxial growth deterministic nanoprocessing devices based on QDs. Furthermore, most promising concepts circuits include active elements applications these novel close an overview open issues outlook future developments.

Language: Английский

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Atomically-thin single-photon sources for quantum communication

npj 2D Materials and Applications, Journal Year: 2023, Volume and Issue: 7(1)

Published: Jan. 27, 2023

To date, quantum communication widely relies on attenuated lasers for secret key generation. In future networks fundamental limitations resulting from their probabilistic photon distribution must be overcome by using deterministic light sources. Confined excitons in monolayers of transition metal dichalcogenides (TMDCs) constitute an emerging type emitter These atomically-thin solid-state sources show appealing prospects large-scale and low-cost device integration, meeting the demands information technologies. Here, we pioneer practical suitability TMDC devices communication. We employ a $\mathrm{WSe}_2$ monolayer single-photon source to emulate BB84 protocol (QKD) setup achieve click rates up 66.95 kHz antibunching values down 0.034 - performance competitive with QKD experiments semiconductor dots or color centers diamond. Our work opens route towards wider applications technologies

Language: Английский

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Purcell-enhanced single photons at telecom wavelengths from a quantum dot in a photonic crystal cavity

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: Feb. 23, 2024

Quantum dots are promising candidates for telecom single photon sources due to their tunable emission across the different low-loss telecommunications bands, making them compatible with existing fiber networks. Their suitability integration into photonic structures allows enhanced brightness through Purcell effect, supporting efficient quantum communication technologies. Our work focuses on InAs/InP QDs created via droplet epitaxy MOVPE operate within telecoms C-band. We observe a short radiative lifetime of 340 ps, arising from factor 5, owing QD low-mode-volume crystal cavity. Through in-situ control sample temperature, we show both temperature tuning QD's wavelength and preserved purity at temperatures up 25K. These findings suggest viability QD-based, cryogen-free C-band sources, applicability in

Language: Английский

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Single-emitter quantum key distribution over 175 km of fibre with optimised finite key rates

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: June 16, 2023

Quantum key distribution with solid-state single-photon emitters is gaining traction due to their rapidly improving performance and compatibility future quantum networks. Here we emulate a scheme quantum-dot-generated single photons frequency-converted 1550 nm, achieving count rates of 1.6 MHz [Formula: see text] asymptotic positive over 175 km telecom fibre. We show that the commonly used finite-key analysis for non-decoy state QKD drastically overestimates secure acquisition times overly loose bounds on statistical fluctuations. Using tighter multiplicative Chernoff bound constrain estimated finite parameters, reduce required number received signals by factor 108. The resulting rate approaches limit at all achievable distances in one hour, 100 generate keys 13 kbps minute acquisition. This result an important step towards long-distance single-emitter networking.

Language: Английский

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Quantum Key Distribution Using a Quantum Emitter in Hexagonal Boron Nitride

Advanced Quantum Technologies, Journal Year: 2023, Volume and Issue: 6(9)

Published: June 22, 2023

Abstract Quantum key distribution (QKD) is considered the most immediate application to be widely implemented among a variety of potential quantum technologies. QKD enables sharing secret keys between distant users by using photons as information carriers. An ongoing endeavor implement these protocols in practice robust, and compact manner so efficiently deployable range real‐world scenarios. Single photon sources (SPS) solid‐state materials are prime candidates this respect. This article demonstrates room temperature, discrete‐variable system bright single source hexagonal‐boron nitride, operating free‐space. Employing an easily interchangeable system, with one million bits length, approximately 70000 bits, at bit error rate 6%, ε‐security 10 −10 generated. study first proof concept finite‐key BB84 realized hBN defects.

Language: Английский

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High-rate intercity quantum key distribution with a semiconductor single-photon source

Light Science & Applications, Journal Year: 2024, Volume and Issue: 13(1)

Published: July 2, 2024

Abstract Quantum key distribution (QKD) enables the transmission of information that is secure against general attacks by eavesdroppers. The use on-demand quantum light sources in QKD protocols expected to help improve security and maximum tolerable loss. Semiconductor dots (QDs) are a promising building block for communication applications because deterministic emission single photons with high brightness low multiphoton contribution. Here we report on first intercity experiment using bright photon source. A BB84 protocol based polarisation encoding realised high-rate telecommunication C-band emitted from semiconductor QD embedded circular Bragg grating structure. Utilising 79 km long link 25.49 dB loss (equivalent 130 direct-connected optical fibre) between German cities Hannover Braunschweig, record-high secret bits per pulse 4.8 × 10 −5 an average bit error ratio ~ 0.65% demonstrated. An asymptotic 28.11 found, corresponding length 144 standard fibre. Deterministic therefore challenge state-of-the-art have potential excel measurement device independent repeater applications.

Language: Английский

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A fiber-pigtailed quantum dot device generating indistinguishable photons at GHz clock-rates

Nanophotonics, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 3, 2025

Abstract Solid-state quantum light sources based on semiconductor dots (QDs) are increasingly employed in photonic information applications. Especially when moving towards real-world scenarios outside shielded lab environments, the efficient and robust coupling of nanophotonic devices to single-mode optical fibers offers substantial advantage by enabling “plug-and-play” operation. In this work we present a fiber-pigtailed cavity-enhanced source flying qubits emitting single indistinguishable photons at clock-rates exceeding 1 GHz. This is achieved employing fully deterministic technique for fiber-pigtailing optimized QD-devices hybrid circular Bragg grating (hCBG) micro-cavities. The fabricated hCBGs feature emission lifetimes < 80 ${< } 80$ ps, corresponding Purcell factor ∼9, suppression multi-photon events with g (2) (0) < %, photon-indistinguishability > ${ >} % measured single-photon efficiency 53 high numerical aperture fiber, 1.2 Megaclicks per second detectors under 80 MHz excitation clock-rates. Furthermore, show that indistinguishability prevail Our results Purcell-enhanced hCBG cavities prime candidate applications science.

Language: Английский

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Plug‐and‐Play Single‐Photon Devices with Efficient Fiber‐Quantum Dot Interface

Advanced Quantum Technologies, Journal Year: 2022, Volume and Issue: 5(10)

Published: Aug. 7, 2022

Incorporating solid-state quantum emitters into optical fiber networks enables the long-distance transmission of information and remote connection distributed nodes. However, interfacing with optics encounters several challenges, including low coupling efficiency stability. Here, we demonstrate a highly efficient fiber-interfacing photonic device that directly launches single photons from dots standard FC/PC-connectorized single-mode (SMF28). Optimally designed structures based on hole gratings produce an ultra-narrow directional beam matches small numerical aperture fiber. A pick-and-place technique selectively integrates miniaturized core Our approach realizes plug-and-play single-photon does not require any alignment thus guarantees long-term The results represent major step toward practical reliable lights across network.

Language: Английский

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Daylight entanglement-based quantum key distribution with a quantum dot source

Quantum Science and Technology, Journal Year: 2022, Volume and Issue: 8(2), P. 025002 - 025002

Published: Dec. 23, 2022

Abstract Entanglement-based quantum key distribution can enable secure communication in trusted node-free networks and over long distances. Although implementations exist both fiber free space, the latter approach is often considered challenging due to environmental factors. Here, we implement a protocol during daytime for first time using dot source. This technology presents advantages terms of narrower spectral bandwidth—beneficial filtering out sunlight—and negligible multiphoton emission at peak brightness. We demonstrate continuous operation course three days, across an urban 270 m-long free-space optical link, under different light weather conditions.

Language: Английский

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