Responsivity

About: Responsivity is a research topic. Over the lifetime, 9918 publications have been published within this topic receiving 186118 citations.

Single-crystalline cubic MgZnO films and their application in deep-ultraviolet optoelectronic devices

Abstract: By employing a relatively low growth temperature and oxygen-rich conditions, single-crystalline cubic MgZnO films were prepared. A solar-blind deep ultraviolet (DUV) photodetector was finished on the MgZnO film. The maximum responsivity of the photodetector is 396 mA/W at 10 V bias, which is almost three orders of magnitude larger than the highest value ever reported in MgZnO-based solar-blind photodetectors. The dark current density is 1.5×10−11 A/cm2, comparable with the smallest value ever reported in solar-blind photodetectors. The improved performance reveals that the single-crystalline cubic MgZnO films have great potential applications in DUV optoelectronic devices.

Low dark current quantum-dot infrared photodetectors with an AlGaAs current blocking layer

Abstract: Low dark current InAs/GaAs quantum-dot infrared photodetectors (QDIPs) are demonstrated. The dark current is reduced by over three orders of magnitude by using a thin AlGaAs current blocking layer. This thin AlGaAs layer reduces the dark current much more than the response signal. The responsivity at 0.5 V is 0.08 A/W with a peak detection wavelength at 6.5μm. The corresponding detectivity is 2.5×109 cm Hz1/2/W1/2, which is the highest detectivity reported for a QDIP at 77 K.

Surface plasmon-enhanced nanopillar photodetectors.

Abstract: We demonstrate nanopillar- (NP) based plasmon-enhanced photodetectors (NP-PEPDs) operating in the near-infrared spectral regime. A novel fabrication technique produces subwavelength elongated nanoholes in a metal surface self-aligned to patterned NP arrays that acts as a 2D plasmonic crystal. Surface plasmon Polariton Bloch waves (SPP-BWs) are excited by the metal nanohole array resulting in electric field intensity “hot spots” in the NP. The NP periodicity determines the peak responsivity wavelength while the nanohole asymmetry produces polarization-dependent coupling of the SPP-BW modes. Resulting photodetectors have 0.28 A/W responsivity peaked at 1100 nm at a reverse bias of −5 V. Designs for further increasing the optical coupling efficiency into the nanopillar are explored. This technology has potential applications for plasmonically enhanced focal plane arrays and plasmonic photovoltaics.

Temperature effects on characteristics and performance of near-infrared wide bandwidth for different avalanche photodiodes structures

Abstract: In this paper, the influences of thermal and spectral variations on various structures of avalanche photodiodes (APDs) have been deeply investigated. The characteristics and performance of Silicon (Si), Gallium Arsenide (GaAs) and Indium Gallium Arsenide (InGaAs) avalanche photodiodes have been evaluated under effects of different temperature degrees. The impacts of different temperature levels on the band gap energy, detector responsivity, noise equivalent power (NEP), cut-off wavelength, dark current and the photocurrent are studied and analyzed in details. The signal to noise ratio (SNR) and Bit Error Rate (BER) of these APDs are also computed and measured under the influences of different temperature levels and spectral variations. The aim of this paper is to determine the most efficient avalanche photodiode achieving the best performance according to the maximum SNR and minimum BER at high temperature environments. The analysis of the proposed model is performed by MATLAB. It was found that the experimental measured results endorse the analytical computed results. Further, it was observed that the APD (InGaAs) provides performance better than other APD structures in terms of larger SNR and less BER at higher temperature levels. Also, the temperature has a slight effect on the performance of APD (GaAs). So, it is seemed to be stable more than other APD structures and recommended to be used in warm environments and for high temperature applications.