Abstrad--Scalar measurements at 1.3 pm of high-speed ( > 20 GHz -3-dB optical bandwidth) photodetector transfer function magnitudes by swept frequency and short pulse (<3-ps FWHM) response techniques are presented and shown to be in excellent agreement to beyond 30 GHz. Scalar deconvolution is used to obtain photodetector response from the pulse response measurements with effects of the measure...

An n-well ion-implanted resistor is shown to work as a very-linear high-gain photodetector at 4.2 K. We take advantage of freeze-out and light-assisted carrier ionisation effects to create a photodetector with a current-gain factor G from 1 x 1 0 ~ to 1 . 6 ~ 1 0 ~ . Experimental results show that at the current gain of 1.6x106, excellent linearity in optical response is obtained when the resis...

The advent of nanophotonics allows devising and fabricating optical antenna as the advanced optical structures that can enhance light–matter interaction in quantum structures such as quantum wells. Improving infrared photodetector performance is discussed theoretically in this paper. We also investigate our recent demonstration of optical antenna integrated on quantum well infrared photodetecto...

Asrar, Pouya, "Investigation of microscale particles using a microfluidic flow cytometer equipped with a sensitive photodetector"

A laser Doppler vibrometer with single photodetector is introduced to measure the vibration on multiple points of target simultaneously. A 2 x 5 beam array with various frequency shifts is generated by three acousto-optic devices, illuminating different points on a vibrating object. The reflected beams interfere with a reference beam on a high-speed photodetector, and the signal is amplified an...

We describe a simple, stable, and high-resolution surface plasmon resonance ~SPR! sensor using a quadrant cell photodetector. The sensor focuses a diode laser through a prism onto a gold film that is divided into two areas, one for reference and the other for sensing analyte. The angular shifts of the SPR generated in the two areas are detected with a quadrant cell photodetector. Because signal...

One-dimensional crystal growth enables the epitaxial integration of III-V compound semiconductors onto a silicon (Si) substrate despite significant lattice mismatch. Here, we report a short-wavelength infrared (SWIR, 1.4-3 μm) photodetector that employs InAs nanowires (NWs) grown on Si. The wafer-scale epitaxial InAs NWs form on the Si substrate without a metal catalyst or pattern assistance; t...

This paper describes the design, fabrication, and measurement of backward-wave-cancelled distributed traveling-wave photodetectors. One of the fundamental issues in traveling-wave photodetectors is the generation of backward-waves, which reduces bandwidth or, in the case of matched input termination, reduces their radio-frequency (RF) efficiencies by up to 6 dB. We report a traveling-wave photo...

In this paper, a single ZnO microwire-based photodetector for the monitoring of ultraviolet (UV) radiation is described. Single crystal ZnO microwires were synthesized using a chemical vapor deposition (CVD) on the Si or Al2O3 substrate. The UV photodetector was fabricated by using in-situ lift-out method in a focused ion beam system to manipulate individual zinc oxide microwire. The photodetec...

We report the fabrication and optical response of boron-doped single silicon nanowire-based metal-semiconductor-metal photodetector. Typical single nanowire devices with diameter of ∼80-100 nm and electrode spacing of ∼1 μm were made using electron-beam lithography from nanowires, grown by a metal-assisted chemical etching process. A high responsivity, of the order of 10(4) A W(-1), was observe...