Single-photon detectors with picosecond timing resolution have advanced rapidly in the past decade. This has spurred progress time-correlated single-photon counting applications, from quantum optics to life sciences and remote sensing. A variety of optoelectronic device architectures offer not only high-performance single-pixel devices but also ability scale up detector arrays extend sensitivity into short-wave infrared beyond. The advent focal plane is poised revolutionize imaging In this...

The use of a high-growth-temperature GaAs spacer layer is demonstrated to significantly improve the performance 1.3μm multilayer self-assembled InAs∕InGaAs dot-in-a-well lasers. inhibits threading dislocation formation, resulting in enhanced electrical and optical characteristics. Incorporation these layers allows fabrication quantum-dot devices emitting above 1.3μm, with extremely low room-temperature threshold current densities operation up 105°C.

This paper describes the design, fabrication, and performance of planar-geometry InGaAs-InP devices which were specifically developed for single-photon detection at a wavelength 1550 nm. General issues such as dark count rate, efficiency, afterpulsing, jitter are described.

The structural and optical properties of GaAs1−xBix alloys for x up to 0.108 have been investigated by high resolution X-ray diffraction photoluminescence (PL). At room temperature (RT), the PL intensity GaAs0.97Bi0.03 sample was found be ∼300 times higher than a GaAs control grown at same (400 °C). measurements carried out 10 K show that when excitation power, Pex increased from 0.11 1140 W cm−2, peak energy blue-shifts 80 meV while full-width-at-half-maximum reduces 115 63 meV. However,...

It is demonstrated that the emission of InAs quantum dots (QDs) capped with GaAsSb can be extended from 1.28to1.6μm by increasing Sb composition capping layer 14% to 26%. Photoluminescence excitation spectroscopy applied investigate nature this large redshift. The dominant mechanism shown formation a type-II transition between an electron state in QDs and hole layer. prospects for using these structures fabricate 1.55μm injection lasers are discussed.

Simple analytical expressions for temperature coefficients of breakdown voltage avalanche photodiodes (APDs) utilizing InP or InAlAs are reported. The work is based on measurements dependence in a series and diodes at temperatures between 20 375 K. While becomes more sensitive with region thickness both materials, the less to changes compared diodes.

Photomultiplication measurements using 244- and 325-nm excitation have been undertaken on a series of thick 4H-SiC avalanche diodes. With widths between 2.7 6 mum the ability to measure multiplication as low 1.001, much wider electric field range has covered than reported date. The results show that hole ionization coefficient (beta) can be obtained with high degree accuracy down fields ~0.9 MV/cm. value electron (alpha) determined from mixed carrier characteristics, beta/alpha ratio is...

Avalanche multiplication and excess noise arising from both electron hole injection have been measured on a series of In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.52</sub> Al xmlns:xlink="http://www.w3.org/1999/xlink">0.48</sub> As p <sup xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> -i-n n -i-p diodes with nominal avalanche region widths between 0.1 2.5 mum. With pure injection, low was at values corresponding to effective...

GaAs1−xBix alloys grown by molecular beam epitaxy for x up to 0.06 were studied photoluminescence (PL). The results indicate that dilute fractions of bismuth (Bi) with &amp;lt; 0.025 improve the material quality this low temperature growth reducing density gallium (Ga) and/or arsenic related defects. crystal starts degrade at higher Bi concentration probably due significant amount Bi-related defects, BiGa. However, room PL intensity continues increase content range greater band-gap offset...

The effects of rapid thermal annealing on the optical and structural properties GaAs1-xBix alloys for x ranging from 0.022 to 0.065 were investigated. At room temperature, annealed showed modest improvement (∼3 times) in photoluminescence (PL) while PL peak wavelength remained relatively unchanged. It was found that bismuth related defects are not easily removed by may be dominated reduction other types including arsenic gallium defects. Also, optimum temperature is Bi composition dependent....

The absorption properties of a series <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${\rm GaAs}_{1-x}{\rm Bi}_{x}$</tex></formula> layers with Notation="TeX">${\sim}{6}\%$</tex></formula> Bi have been systematically investigated by measuring photocurrent spectra in p-i-n diode structures grown molecular beam epitaxy. xmlns:xlink="http://www.w3.org/1999/xlink"> <tex varied thickness from 50 to 350 nm...

An extremely low noise Separate Absorption and Multiplication Avalanche Photodiode (SAM-APD), consisting of a GaAs0.52Sb0.48 absorption region an Al0.85Ga0.15As0.56Sb0.44 avalanche region, is reported. The device incorporated appropriate doping profile to suppress tunneling current from the achieving large gain, ∼130 at room temperature. It exhibits excess factors 1.52 2.48 gain 10 20, respectively. At our measured factor more than three times lower that in commercial InGaAs/InP SAM-APD....

Near-infrared linear mode Al <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\text{0.85}}$</tex-math> </inline-formula> Ga notation="LaTeX">$_{\text{0.15}}$</tex-math> As notation="LaTeX">$_{\text{0.56}}$</tex-math> Sb notation="LaTeX">$_{\text{0.44}}$</tex-math> avalanche photodiodes (APDs) exhibit excellent temperature stability, potentially simplifying Geiger operation. We have carried out the first...

A systematic study of avalanche multiplication on a series In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.52</sub> Al xmlns:xlink="http://www.w3.org/1999/xlink">0.48</sub> As p <sup xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> -i-n and n -i-p diodes with nominal intrinsic region thicknesses ranging from 0.1 to 2.5 mum has been used deduce effective ionization coefficients between 220 980 kVmiddotcm...

We report excess noise factors measured on a series of InP diodes with varying avalanche region thickness, covering wide electric field range from 180 to 850 kV/cm. The increased significance dead space in thin thickness decreases the noise. An factor F = 3.5 at multiplication M 10 was measured, lowest value reported so far for InP. dependence impact ionization coefficients and threshold energies have been determined using non-local model take into account effects. This work suggests that...

Increasing reliance on the Internet places greater and demands for high-speed optical communication systems.Increasing their data transfer rate allows more to be transferred over existing links.With receivers being essential all links, bandwidth performance of key components in receivers, such as avalanche photodiodes (APDs), must improved.The APDs rely In0.53Ga0.47As(grown lattice-matched InP substrates) efficiently absorb detect signals with 1310 or 1550 nm wavelength, optimal wavelengths...

A single photon avalanche diode (SPAD) with an InGaAs absorption region, and InAlAs region was designed demonstrated to detect 1550 nm wavelength photons. The characterization included leakage current, dark count rate detection efficiency as functions of temperature from 210 294 K. SPAD exhibited good stability, breakdown voltage dependence approximately 45 mV K −1 . Operating at in a gated mode, the achieved probability 26% 1 × 10 8 Hz. time response showed decreasing timing jitter (full...

Photoluminescence (PL) of GaAs0.97Bi0.03 alloy was measured over a wide range temperatures and excitation powers. Room temperature PL with peak wavelength 1038 nm full-width-half-maximum 75 meV observed which is relatively low for this composition. The improved quality believed due to reduced fluctuations by growing at high temperature. dependence energy indicated significant exciton localization temperatures. Furthermore, the band gap found be weaker than GaAs. An analysis dominant carrier...

The noise sources affecting Al0.8Ga0.2As and GaAs spectroscopic X-ray photon counting p+–i–n+ photodiodes connected to a custom low-noise charge sensitive preamplifier are quantified by analysing the system's response pulses from signal generator varying shaping amplifier's time (from 0.5 μs 10 μs). system is investigated at three temperatures (−10 °C, +20 °C +50 °C) in order characterise variation of component optimum with temperature for diodes. analysis shows that primarily limited...

Electrical characterization of two GaAs p+-i-n+ mesa X-ray photodiodes over the temperature range 0 °C to 120 together with one diodes as an detector 60 is reported part development photon counting spectroscopic systems for harsh environments. The randomly selected were fully etched and unpassivated. 200 μm in diameter had 7 thick i layers. leakage current density was found increase from (3 ± 1) nA/cm−2 at (24.36 0.05) μA/cm−2 D1 a smaller than uncertainty (0.2 1.2) (9.39 0.02) D2 maximum...

The effects of dead space (the minimum distance travelled by a carrier before acquiring enough energy to impact ionize) on the current impulse response and bandwidth an avalanche multiplication process are obtained from numerical model that maintains constant velocity but allows for random distribution ionization path lengths. results show main mechanism responsible increase in time with is number groups, which qualitatively describes length chains. When negligible, follows behavior...