Locally oxidized silicon surface-plasmon Schottky detector for telecom regime.

We experimentally demonstrate an on-chip nanoscale silicon surface-plasmon Schottky photodetector based on internal photoemission process and operating at telecom wavelengths. The device is fabricated using a self-aligned approach of local-oxidation of silicon (LOCOS) on silicon on insulator substrate, which provides compatibility with standard complementary metal-oxide semiconductor technology and enables the realization of the photodetector and low-loss bus photonic waveguide at the same fabrication step. Additionally, LOCOS technique allows avoiding lateral misalignment between the silicon surface and the metal layer to form a nanoscale Schottky contact. The fabricated devices showed enhanced detection capability for shorter wavelengths that is attributed to increased probability of the internal photoemission process. We found the responsivity of the nanodetector to be 0.25 and 13.3 mA/W for incident optical wavelengths of 1.55 and 1.31 μm, respectively. The presented device can be integrated with other nanophotonic and nanoplasmonic structures for the realization of monolithic opto-electronic circuitry on-chip.

Silicon-metal waveguide as a high efficiency Schottky detector for telecom wavelengths

We demonstrate an integrated on-chip compact and high efficiency Schottky detector for telecom wavelengths based on silicon metal waveguide. Detection is based on the internal photoemission process. Theory and experimental results are discussed. © 2012 OSA.

On chip plasmonic enhanced silicon Schottky detector for telecom wavelengths

We demonstrate an integrated on-chip plasmonic enhanced Schottky detector for telecom wavelengths based on the internal photoemission process. This CMOS compatible device may serve as a promising alternative to the Si-Ge detectors. © 2012 OSA.

Locally-oxidized silicon surface-plasmon Schottky detector for telecom wavelengths

We demonstrate an integrated on-chip locally-oxidized silicon surface-plasmon Schottky detector for telecom wavelengths based on the internal photoemission process. Theoretical model and experimental results will be presented and discussed. © 2011 IEEE.

Locally oxidized silicon surface-plasmon Schottky detector for telecom regime

We experimentally demonstrate an on-chip nanoscale silicon surface-plasmon Schottky photodetector based on internal photoemission process and operating at telecom wavelengths. The device is fabricated using a self-aligned approach of local-oxidation of silicon (LOCOS) on silicon on insulator substrate, which provides compatibility with standard complementary metal-oxide semiconductor technology and enables the realization of the photodetector and low-loss bus photonic waveguide at the same fabrication step. Additionally, LOCOS technique allows avoiding lateral misalignment between the silicon surface and the metal layer to form a nanoscale Schottky contact. The fabricated devices showed enhanced detection capability for shorter wavelengths that is attributed to increased probability of the internal photoemission process. We found the responsivity of the nanodetector to be 0.25 and 13.3 mA/W for incident optical wavelengths of 1.55 and 1.31 μm, respectively. The presented device can be integrated with other nanophotonic and nanoplasmonic structures for the realization of monolithic opto-electronic circuitry on-chip. © 2011 American Chemical Society.

Highly efficient detector of the neurotransmitter ACh and AChE inhibitors

Among the variety of applications for biosensors one of the exciting frontiers is to utilize those devices as post-synaptic sensing elements in chemical coupling between neurons and solid-state systems. The first necessary step to attain this challenge is to realize highly efficient detector for neurotransmitter acetylcholine (ACh). Herein, we demonstrate that the combination of floating gate configuration of ion-sensitive field effect transistor (ISFET) together with diluted covalent anchoring of enzyme acetylcholinesterase (AChE) onto device sensing area reveals a remarkable improvement of a four orders of magnitude in dose response to ACh. This high range sensitivity in addition to the benefits of peculiar microelectronic design show, that the presented hybrid provides a competent platform for assembly of artificial chemical synapse junction. Furthermore, our system exhibits clear response to eserine, a competitive inhibitor of AChE, and therefore it can be implemented as an effective sensor of pharmacological reagents, organophosphates, and nerve gases as well. © 2007 Materials Research Society.

On chip plasmonic enhanced silicon schottky detector for telecom wavelengths

We demonstrate an integrated on-chip plasmonic enhanced Schottky detector for telecom wavelengths based on the internal photoemission process. This CMOS compatible device may serve as a promising alternative to the Si-Ge detectors. © 2011 Optical Society of America.

Silicon-metal waveguide as a high efficiency schottky detector for telecom wavelengths

We demonstrate an integrated on-chip compact and high efficiency Schottky detector for telecom wavelengths based on silicon metal waveguide. Detection is based on the internal photoemission process. Theory and experimental results are discussed. © 2012 Optical Society of America.

Locally-oxidized silicon surface-plasmon Schottky detector for telecom wavelengths

We demonstrate an integrated on-chip locally-oxidized silicon surface-plasmon Schottky detector for telecom wavelengths based on the internal photoemission process. Theoretical model and experimental results will be presented and discussed. © 2011 Optical Society of America.

SHORT PERIOD InAs/GaSb SUPERLATTICE INFRARED DETECTOR ON GaAs SUBSTRATES

Two type II superlattices (SLs) InAs(2ML)/GaSb(8ML) and InAs(8ML)/GaSb(8ML) were grown on GaAs substrates by molecular-beam epitaxy. High resolution X-ray diffraction showed the periods of the two SLs were 31.2 angstrom and 57.3 angstrom, respectively. Room-temperature optical transmittance spectra showed that there were clear absorption edges at 2.1 mu m and 5 mu m for the two SLs. The SWIR and MWIR photoconductor devices were fabricated by standard lithography and etched by tartaric acid solution. The spectral response and blackbody tests were carried out at low and room temperatues. The results show that the 50% cutoff wavelengths of the two photoconductors are 2.1 mu m and 5.0 mu m respectively and D-bb* is above 2 x 10(8) cmHz(1/2)/W for two kinds of photoconductors at 77K. D-bb* is above 10(8) cmHz(1/2)/W for SWIR photoconductor at room temperature.

Influence of penetrating V-pits on leakage current of GaN based p-i-n UV detector

The leakage mechanism of GaN-based p-i-n (p-AlGaN/i-GaN/n-GaN) UV detector has been investigated. With the same dislocation density, devices made from material with higher density of V-pits on surface produce larger leakage current. SEM images show that some V-pits penetrate into i-GaN layer, sometimes even the n-GaN layer. If p-ohmic contact metal (Ni/Au) deposits in the V-pits, Schottky contact would be formed at the interface of metal and i-GaN, or form ohmic contact at the interface of metal and n-GaN. The existence of parallel Schottky junction and ohmic contact resistance enhances the leakage current greatly.

1.55 mu m Ge islands resonant-cavity-enhanced detector with high-reflectivity bottom mirror

A 1.55 mum Ge islands resonant-cavity-enhanced (RCE) detector with high-reflectivity bottom mirror was fabricated by a simple method. The bottom mirror was deposited in the hole formed by anisotropically etching in a basic solution from the back side of the sample with the buried SiO2 layer in silicon-on-insulator substrate as the etch-stop layer. Reflectivity spectrum indicates that the mirror deposited in the hole has a reflectivity as high as 99% in the range of 1.2-1.65 mum. The peak responsivity of the RCE detector at 1543.8 nm is 0.028 mA/W and a full width at half maximum of 5 nm is obtained. Compared with the conventional p-i-n photodetector, the responsivity of RCE detector has a nearly threefold enhancement. (C) 2004 American Institute of Physics.

Detector-induced dephasing in quantum-dot cellular automata qubit

We investigate the quantum dynamics of the quantum-dot cellular automata qubit in the presence of a quantum point contact detector by modified rate equations. It is demonstrated that the qubit information can be resolved by measuring the detector current variation. Furthermore, we show that this oscillating current and the electron occupation probabilities in states \b> and \c> decay drastically as the dephasing rate increases, clearly revealing the influence of the dephasing induced by the detector. Moreover, it is shown that the operation speed of the quantum-dot cellular automata qubit may be adjusted by varying the interdot coupling strength. (C) 2003 American Institute of Physics.

Absolute measurement of detector quantum efficiency using optical parametric down-conversion pumped by femtosecond laser pulses

Absolute measurement of detector quantum efficiency using optical parametric down-conversion has been extensively studied for the case of a continuous wave pump. In this paper, we have used the temporally and spatially correlated properties of the down-converted photon pairs generated in a nonlinear crystal pumped by a femtosecond laser pulse to perform an absolute measurement of detector quantum efficiency. The measured detector quantum efficiency is in excellent agreement with the measured value in the conventional way. A lens with a long focal length was adopted for efficiently increasing the intensity of the down-conversion entangled photon source.