High Single-photon Detection Efficiency Research Articles

Simulation of High-Efficiency Resonant-Cavity-Enhanced GeSn Single-Photon Avalanche Photodiodes for Sensing and Optical Quantum Applications

Two novel resonant-cavity-enhanced (RCE) GeSn single-photon avalanche photodiode (SPAD) detectors are designed and simulated for high-efficiency single-photon detection at 1550 and 2000 nm wavelength at room temperature for sensing and optical quantum applications. The RCE GeSn SPAD consists of a PIPIN GeSn/Si heterostructures embedded in an optical cavity formed by a distributed Bragg reflector (DBR) and GeSn surface. The results show that high photon absorption efficiency and avalanche triggering probabilities can be achieved by careful design of DBR reflectors, GeSn absorber, doping concentrations of Si charge sheet layer and multiplication layer, which lead to a high single-photon detection efficiency (SPDE) of ~80%, which is promising for emerging quantum applications demanding high SPDE, such as linear optical quantum computing. The noise equivalent power (NEP) and dark count rate (DCR) as a function of threading dislocations density (TDD) are examined as well. It is found that the device could operate near room temperature with a similar DCR level to that of Ge SPAD operating at low temperature. A NEP of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 3\times 10^{-15}$ </tex-math></inline-formula> W/Hz <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{1/2}$ </tex-math></inline-formula> is observed from RCE GeSn SPAD for 1550 nm wavelength at room temperature. This work shows that the proposed RCE GeSn SPADs are promising candidates for high-efficiency single-photon detection in short-wave infrared (SWIR) regime for sensing and optical quantum applications.

Theoretical Prediction of High-Performance Room-Temperature InGaAs/Si Single-Photon Avalanche Diode Fabricated by Semiconductor Interlayer Bonding

Single-photon avalanche diode (SPAD) is an ultrasensitive device for the detection of weak signals. Epitaxial InP-based devices exhibit poor avalanche characteristics and poor compatibility with Si complementary metal oxide semiconductor (CMOS) circuit, and epitaxial Si-based devices show high dark count rate (DCR) and limited detection wavelength. Here we first show a new generation of InGaAs-on-Si SPADs, achieved by semiconductor interlayer bonding, for the detection of 1550-nm infrared signals theoretically. This wafer-bonded InGaAs/Si SPAD has enabled a significant step-change in performance. The dark current of this SPAD is four orders of magnitude lower than that of the epitaxial ones (300 K). High gain-bandwidth-product of 254 and 353 GHz is achieved at the gain of ~ 24 and ~ 36, respectively, for the wafer-bonded SPAD with polycrystalline Si bonding layer at InGaAs/Si bonded interface. In comparison with epitaxial SPADs, the wafer-bonded ones exhibit low DCR ( ~ 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> Hz at 10% V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">br</sub> ), high single photon detection efficiency ( ~ 24% at 10% V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">br</sub> ), and high pulse repetition rate (1 GHz at 5% V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">br</sub> ) at 300 K. These results indicate that utilizing the wafer-bonded platform, the route toward high-performance InGaAs-on-Si SPAD arrays for use in future eye-safe laser radar (LIDAR) and quantum communication at room temperature (RT) is expected to be achieved.

A light approach to quantum advantage

Quantum Computing Quantum computational advantage or supremacy is a long-anticipated milestone toward practical quantum computers. Recent work claimed to have reached this point, but subsequent work managed to speed up the classical simulation and pointed toward a sample size–dependent loophole. Quantum computational advantage, rather than being a one-shot experimental proof, will be the result of a long-term competition between quantum devices and classical simulation. Zhong et al. sent 50 indistinguishable single-mode squeezed states into a 100-mode ultralow-loss interferometer and sampled the output using 100 high-efficiency single-photon detectors. By obtaining up to 76-photon coincidence, yielding a state space dimension of about 1030, they measured a sampling rate that is about 1014-fold faster than using state-of-the-art classical simulation strategies and supercomputers. Science , this issue p. [1460][1] [1]: /lookup/doi/10.1126/science.abe8770

Quantum computational advantage using photons.

Quantum computers promise to perform certain tasks that are believed to be intractable to classical computers. Boson sampling is such a task and is considered a strong candidate to demonstrate the quantum computational advantage. We performed Gaussian boson sampling by sending 50 indistinguishable single-mode squeezed states into a 100-mode ultralow-loss interferometer with full connectivity and random matrix-the whole optical setup is phase-locked-and sampling the output using 100 high-efficiency single-photon detectors. The obtained samples were validated against plausible hypotheses exploiting thermal states, distinguishable photons, and uniform distribution. The photonic quantum computer, Jiuzhang, generates up to 76 output photon clicks, which yields an output state-space dimension of 1030 and a sampling rate that is faster than using the state-of-the-art simulation strategy and supercomputers by a factor of ~1014.

Polarization Independent High Absorption Efficiency Single-Photon Detectors Based on Three-Dimensional Integrated Superconducting And Plasmonic Patterns

Three-dimensional superconducting nanowire single-photon detectors (SNSPDs) composed of two-dimensional plasmonic gratings integrated into two one-dimensional periodic and vertically shifted patterns of absorbing niobium-nitride nanowires were optimized numerically. Their potential to achieve high infrared absorptance polarization independently was proven. Advantages of vertical-wall, tilted-wall and in-substrate deepening gold antenna segments were compared. The highest ∼93% polarization independent absorptance maximum was achieved exactly at the desired 1550 nm in nano-cavity-double-deflector grating integrated SNSPDs with 1.003 (0.997) polarization contrast at perpendicular incidence in 0° (90°) azimuthal orientation. This device exhibits the smallest polarization dependence throughout the complete azimuthal angle and the inspected wavelength intervals.

Development of a high-resolution and high-efficiency single-photon detector for studying cardiovascular diseases in mice

SPECT systems using pinhole apertures permit radiolabeled molecular distributions to be imaged in vivo in small animals. Nevertheless studying cardiovascular diseases by means of small animal models is very challenging. Specifically, submillimeter spatial resolution, good energy resolution and high sensitivity are required. We designed what we consider the "optimal" radionuclide detector system for this task. It should allow studying both detection of unstable atherosclerotic plaques and monitoring the effect of therapies. Using mice is particularly challenging in situations that require several intravenous injections of radiotracers, possibly for week or even months, in chronically ill animals. Thus, alternative routes of delivering the radiotracer in tail vein should be investigated. In this study we have performed preliminary measurements of detection of atherosclerotic plaques in genetically modified mice with high-resolution prototype detector. We have also evaluated the feasibility of assessing left ventricular perfusion by intraperitoneal delivering of MIBI-Tc in healthy mice.

Incorporating quantum photonic sources and single-photon detectors onto a single chip

Researchers made a high-efficiency single-photon detector on an integrated circuit with a quantum optical source.

Optimizing the stoichiometry of ultrathin NbTiN films for high-performance superconducting nanowire single-photon detectors.

The requirements in quantum optics experiments for high single-photon detection efficiency, low timing jitter, low dark count rate and short dead time have been fulfilled with the development of superconducting nanowire single-photon detectors. Although they offer a detection efficiency above 90%, achieving a high time resolution in devices made of amorphous materials is a challenge, particularly at temperatures above 0.8 K. Devices made from niobium nitride and niobium titanium nitride allow us to reach the best timing jitter but, in turn, have stronger requirements in terms of film quality to achieve a high efficiency. Here we take advantage of the flexibility of reactive co-sputter deposition to tailor the composition of NbxTi1-xN superconducting films and show that a Nb fraction of x = 0.62 allows for the fabrication of detectors from films as thick as 9 nm and covering an active area of 20 µm, with a wide detection saturation plateau at telecom wavelengths and in particular at 1550 nm. This is a signature of an internal detection efficiency saturation, achieved while maintaining the high time resolution associated with NbTiN and operation at 2.5K. With our optimized recipe, we reliably fabricated detectors with high critical current densities reaching a saturation plateau at 1550 nm with 80% system detection efficiency and with a FWHM timing jitter as low as 19.5 ps.

High-Efficiency Thermoelectric Single-Photon Detector Based on Lanthanum and Cerium Hexaborides

A design for a high-efficiency single-photon detector based on lanthanum and cerium hexaborides, which operates from the infrared to ultraviolet spectral ranges, is suggested. The results of computer simulations of heat transfer in the sensitive element of the detector upon the absorption of photons with energies of 0.5–4.13 eV are presented. To attain a high efficiency of the system of photon detection in the wavelength range from near infrared to ultraviolet, lanthanum hexaboride is proposed as the absorber and heat-sink material in the sensitive element. It is shown that a sensitive element of both single- and three-layer design made entirely of hexaborides will possess a gigahertz counting rate and a detection efficiency exceeding 90%.

Fast and high efficiency superconducting nanowire single-photon detector at 630 nm wavelength.

Fast and high efficiency single-photon detectors have important applications in the fields of life science and quantum information. We report, herein, a serially connected two superconducting nanowire avalanche photon detector (SC2-SNAP) fabricated on a dielectric mirror aiming to 630nm wavelength. This detector shows system detection efficiency (SDE) of 84.8% at a dark count rate of 10Hz and offers fast detection speed while maintaining a high SDE, where the counting rate reaches 53.9MHz at an SDE of 60%. This fast and high efficiency single-photon detector may find applications in fluorescence correlation spectroscopy and quantum key distribution.

Высокоэффективный термоэлектрический однофотонный детектор на основе гексаборидов лантана и церия

AbstractA design for a high-efficiency single-photon detector based on lanthanum and cerium hexaborides, which operates from the infrared to ultraviolet spectral ranges, is suggested. The results of computer simulations of heat transfer in the sensitive element of the detector upon the absorption of photons with energies of 0.5–4.13 eV are presented. To attain a high efficiency of the system of photon detection in the wavelength range from near infrared to ultraviolet, lanthanum hexaboride is proposed as the absorber and heat-sink material in the sensitive element. It is shown that a sensitive element of both single- and three-layer design made entirely of hexaborides will possess a gigahertz counting rate and a detection efficiency exceeding 90%.

The MONDO Detector Prototype Development and Test: Steps Toward an SPAD-CMOS-Based Integrated Readout (SBAM Sensor)

The MOnitor for Neutron Dose in hadrOntherapy (MONDO) project addresses the technical challenges posed by a neutron tracker detector aiming for a high detection efficiency and a good backtracking precision. The project aims to develop a tracking device capable of fully reconstructing the four momentum of fast and ultrafast secondary neutrons produced, e.g., in particle therapy (PT) treatments or in other physical processes. The MONDO tracker uses, as active material, squared scintillating fibers readout by dedicated CMOS-based digital single-photon avalanche diode (SPAD) array sensors. The expected light output, when operating in neutron monitoring applications, was experimentally evaluated in order to optimize the design of the MONDO detector readout. A small detector prototype ( $4 \times 4 \times 4.8$ cm) has been built and tested at a test beam facility. The detection capabilities have been measured using a traditional photomultiplier (PMT) and a particle beam of 450-MeV electrons crossing a single layer of fibers. The observed number of photoelectrons in this case is (7.2 ± 1.4). A detector prototype was also tested with an SPAD-based SBAM (SPAD-Based Acquisition readout for MONDO experiment) sensor ( SPADnet-I ) to study the tracking performances. SBAM is a novel sensor developed to match the need of high single-photon detection efficiency and high spatial resolution and compactness. The sensor expected performance is discussed in view of an operation tailored for PT applications. In this contribution, we also report the results of a simulation performed to optimize the full MONDO detector layout.

Multi-beam single-photon-counting three-dimensional imaging lidar.

Photon-counting laser ranging has attracted a lot of research interest for its application in the altimeter. In this letter, we report a large scale multi-beam photon-counting laser imaging system by using 100 laser beams in linear array as the light source. Taking advantage of a 100-channel low-noise high-efficiency single-photon detector, the three-dimensional image of remote targets could be constructed rapidly according to the time-of-flight measurement. This system provides a solution for a high-speed, high-resolution, low energy-consumption pushbroom airborne or spaceborne laser altimeter.

Design of High Speed and High Efficiency Single-Photon Detectors Using Silicon Avalanche Photodiodes

Avalanche photodiodes are crucial materials for single-photon detection. Single-photon detectors are indispensable components for optical experiments and applications such as quantum information processing and quantum communications, both of which demand high single-photon detection efficiency. The authors have first developed a silicon single-photon avalanche detector in near infrared spectrum with 1 MHz square wave gating and tested its performance. Then we have also designed a high-speed and high-efficiency silicon single-photon detection system with 152 MHz sine wave gating and improved its single-photon detection efficiency to 77.48%.

Discrete and continuous variables for measurement-device-independent quantum cryptography

We demonstrate that, with a fair comparison, the secret key rate of discrete-variable measurement-device-independent quantum key distribution (DV-MDI-QKD) with high-efficiency single-photon detectors and good system alignment is typically rather high and thus highly suitable for not only long distance communication but also metropolitan networks. The previous reservation on the key rate and suitability of DV-MDI-QKD for metropolitan networks expressed by Pirandola et al. [Nature Photon. 9, 397 (2015)] was based on an unfair comparison with low-efficiency detectors and high quantum bit error rate, and is, in our opinion, unjustified.

Cryogenic gaseous photomultipliers and liquid hole- multipliers: advances in THGEM-based sensors for future noble-liquid TPCs

Dual-phase noble-liquid TPCs are presently the most sensitive instruments for direct dark matter detection. Scaling up existing ton-scale designs to the multi-ton regime may prove to be technologically challenging. This includes both large-area coverage with affordable high-QE UV-photon detectors, and maintaining high precision in measuring the charge and light signals of rare events with keV-scale energy depositions. We present our recent advances in two complementary approaches to these problems: large-area cryogenic gaseous photomultipliers (GPM) for UV-photon detection, and liquid-hole multipliers (LHM) that provide electroluminescence light in response to ionization electrons and primary scintillation photons, using perforated electrodes immersed within the noble liquid. Results from a 10 cm diameter GPM coupled to a dual-phase liquid- xenon TPC demonstrate the feasibility of recording - for the first time - both primary (“S1”) and secondary (“S2”) scintillation signals, over a very broad dynamic range. The detector, comprising a triple-THGEM structure with CsI on the first element, has been operating stably at 180 K with gains larger than 105; it provided high single-photon detection efficiency - in the presence of massive alpha-particle induced S2 signals; S1 scintillation signals were recorded with time resolutions of 1.2 ns (RMS). Results with the LHM operated in liquid xenon yielded large photon gains, with a pulse-height resolution of 11% (RMS) for alpha-particle induced S2 signals. The detector response was stable over several months. The response of the S2 signals to rapid changes in pressure lead to the conclusion that the underlying mechanism for S2 light is electroluminescence in xenon bubbles trapped below the immersed THGEM electrode. Both studies have the potential of paving the way towards new designs of dual- and single-phase noble-liquid TPCs that could simplify the conception of future multi-ton detectors of dark matter and other rare events.

First results of a large-area cryogenic gaseous photomultiplier coupled to a dual-phase liquid xenon TPC

We discuss recent advances in the development of cryogenic gaseous photomultipliers (GPM), for possible use in dark matter and other rare-event searches using noble-liquid targets. We present results from a 10 cm diameter GPM coupled to a dual-phase liquid xenon (LXe) TPC, demonstrating—for the first time—the feasibility of recording both primary (``S1'') and secondary (``S2'') scintillation signals. The detector comprised a triple Thick Gas Electron Multiplier (THGEM) structure with cesium iodide photocathode on the first element; it was shown to operate stably at 180 K with gains above 105, providing high single-photon detection efficiency even in the presence of large α particle-induced S2 signals comprising thousands of photoelectrons. S1 scintillation signals were recorded with a time resolution of 1.2 ns (RMS). The energy resolution (σ/E) for S2 electroluminescence of 5.5 MeV α particles was ∼ 9%, which is comparable to that obtained in the XENON100 TPC with PMTs. The results are discussed within the context of potential GPM deployment in future multi-ton noble-liquid detectors.

Materials Development for High Efficiency Superconducting Nanowire Single-Photon Detectors

ABSTRACTSuperconducting nanowire single-photon detectors (SNSPDs) based on ultra-thin films have become the preferred technology for applications that require high efficiency single-photon detectors with high speed, high timing resolution, and low dark count rates at near-infrared wavelengths. Since demonstration of the first SNSPD using NbN thin films, an increasingly larger number of materials are being explored. We investigate amorphous thin film alloys of MoSi, MoGe, and WRe with the goal of optimizing SNSPDs for higher operating temperature, high efficiency and high speed. To explore material adequacy for SNSPDs, we have measured superconducting transition temperature (Tc) as a function of film thickness and sheet resistance, as well as critical current densities. In this paper we present our results comparing these materials to WSi, another amorphous material widely used for SNSPD devices.

A superconducting nanowire single photon detector on lithium niobate

Superconducting nanowire single photon detectors (SNSPDs) are a key enabling technology for optical quantum information science. In this paper we demonstrate a SNSPD fabricated on lithium niobate, an important material for high speed integrated photonic circuits. We report a system detection efficiency of 0.15% at a 1 kHz dark count rate with a maximum of ∼1% close to the critical current at 1550 nm wavelength for a parallel wire SNSPD with front side illumination. There is clear scope for improving on this performance with further materials optimization. Detector integration with a lithium niobate optical waveguide is simulated, demonstrating the potential for high single photon detection efficiency in an integrated quantum optic circuit.

Proton Irradiation of 4H-SiC Ultraviolet Single Photon Avalanche Diodes

The effects of proton irradiation on uv 4H-SiC single photon avalanche photodiodes (SPADs) are reported. The SPADs, grown by chemical vapor deposition, were designed for uv operation with dark count rates (DCR) of about 30 kHz and single photon detection efficiency (SPDE) of 4.89%. The SPADs were irradiated with 2 MeV protons to a fluence of 1012 cm-2. After irradiation, the I-V characteristics show forward voltage (&lt;1.9 V) generation-recombination currents 2 to 3 times higher than before irradiation. Single photon counting measurements imply generation-recombination centers created in the band gap after irradiation. For threshold voltage ranging from 23 to 26 mV, the 4H-SiC SPAD showed low DCR (&lt;54 kHz) and high SPDE (&gt;1%) after irradiation. The SPADs demonstrated proton radiation tolerance for geosynchronous space applications.