IMPROVEMENT OF IR PYROELECTRIC DETECTOR PERFORMANCE IN THZ RANGE USING WAVELENGTH-SCALE SPHERE-BASED TERAJET EFFECT

An infrared (IR) pyroelectric detector was investigated for terahertz (THz) detection using the principle of the terajet effect, which focuses the beam beyond the diffraction limit. The terahertz beam was coupled to the detector’s optical window through a two-wavelength-dimension dielectric cubic particle-lens based on the terajet effect. We experimentally demonstrate an enhancement of about 6 dB in the sensitivity under excitation of 0.2 THz without degradation of the noise equivalent power value. The results show that the proposed method could be applied to increase the sensitivity of various commercial IR sensors for THz applications that do not require modification of the internal structure, and it may apply also to acoustics and plasmonic detectors.

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High-purity Ge x-ray detectors: Sensitivity factors and usefulness

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136350 ◽

1990 ◽

Vol 48 (2) ◽

pp. 548-548

Author(s):

E. B. Steel

Keyword(s):

High Purity ◽

High Energy ◽

Quantitative Chemical Analysis ◽

Detector Performance ◽

X Ray ◽

Detector Sensitivity ◽

Specimen Holder ◽

Many Instruments ◽

Charge Resolution ◽

Sensitivity Factors

High Purity Germanium (HPGe) x-ray detectors are now commercially available for the analytical electron microscope (AEM). The detectors have superior efficiency at high x-ray energies and superior resolution compared to traditional lithium-drifted silicon [Si(Li)] detectors. However, just as for the Si(Li), the use of the HPGe detectors requires the determination of sensitivity factors for the quantitative chemical analysis of specimens in the AEM. Detector performance, including incomplete charge, resolution, and durability has been compared to a first generation detector. Sensitivity factors for many elements with atomic numbers 10 through 92 have been determined at 100, 200, and 300 keV. This data is compared to Si(Li) detector sensitivity factors.The overall sensitivity and utility of high energy K-lines are reviewed and discussed. Many instruments have one or more high energy K-line backgrounds that will affect specific analytes. One detector-instrument-specimen holder combination had a consistent Pb K-line background while another had a W K-line background.

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Prospects of Time-Resolved Photon Emission as a Debug Tool

ISTFA 2002: Conference Proceedings from the 28th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2002p0645 ◽

2002 ◽

Author(s):

Jim Vickers ◽

Nader Pakdaman ◽

Steven Kasapi

Keyword(s):

Photon Emission ◽

Photon Counting ◽

Signal Propagation ◽

General Function ◽

Hot Electron ◽

Detector Performance ◽

Time Resolved ◽

Switching Event ◽

Emission System

Abstract Dynamic hot-electron emission using time-resolved photon counting can address the long-term failure analysis and debug requirements of the semiconductor industry's advanced devices. This article identifies the detector performance parameters and components that are required to scale and keep pace with the industry's requirements. It addresses the scalability of dynamic emission with the semiconductor advanced device roadmap. It is important to understand the limitations to determining that a switching event has occurred. The article explains the criteria for event detection, which is suitable for tracking signal propagation and looking for logic or other faults in which timing is not critical. It discusses conditions for event timing, whose goal is to determine accurately when a switching event has occurred, usually for speed path analysis. One of the uses of a dynamic emission system is to identify faults by studying the emission as a general function of time.

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Broadband spectroscopy of astrophysical ice analogues

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935619 ◽

2019 ◽

Vol 629 ◽

pp. A112 ◽

Cited By ~ 8

Author(s):

B. M. Giuliano ◽

A. A. Gavdush ◽

B. Müller ◽

K. I. Zaytsev ◽

T. Grassi ◽

...

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Time Domain ◽

Complex Refractive Index ◽

Far Infrared ◽

Infrared Region ◽

Thz Radiation ◽

The Real ◽

Thz Range ◽

The Time Domain

Context. Reliable, directly measured optical properties of astrophysical ice analogues in the infrared and terahertz (THz) range are missing from the literature. These parameters are of great importance to model the dust continuum radiative transfer in dense and cold regions, where thick ice mantles are present, and are necessary for the interpretation of future observations planned in the far-infrared region. Aims. Coherent THz radiation allows for direct measurement of the complex dielectric function (refractive index) of astrophysically relevant ice species in the THz range. Methods. We recorded the time-domain waveforms and the frequency-domain spectra of reference samples of CO ice, deposited at a temperature of 28.5 K and annealed to 33 K at different thicknesses. We developed a new algorithm to reconstruct the real and imaginary parts of the refractive index from the time-domain THz data. Results. The complex refractive index in the wavelength range 1 mm–150 μm (0.3–2.0 THz) was determined for the studied ice samples, and this index was compared with available data found in the literature. Conclusions. The developed algorithm of reconstructing the real and imaginary parts of the refractive index from the time-domain THz data enables us, for the first time, to determine the optical properties of astrophysical ice analogues without using the Kramers–Kronig relations. The obtained data provide a benchmark to interpret the observational data from current ground-based facilities as well as future space telescope missions, and we used these data to estimate the opacities of the dust grains in presence of CO ice mantles.

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MoS2 Based Photodetectors: A Review

Sensors ◽

10.3390/s21082758 ◽

2021 ◽

Vol 21 (8) ◽

pp. 2758

Author(s):

Alberto Taffelli ◽

Sandra Dirè ◽

Alberto Quaranta ◽

Lucio Pancheri

Keyword(s):

Electric Fields ◽

Spectral Range ◽

Performance Metrics ◽

Transition Metal Dichalcogenides ◽

Visible Spectral Range ◽

Detector Performance ◽

Strong Light ◽

Near Ultraviolet ◽

Passivation Layers ◽

Low Dimensional

Photodetectors based on transition metal dichalcogenides (TMDs) have been widely reported in the literature and molybdenum disulfide (MoS2) has been the most extensively explored for photodetection applications. The properties of MoS2, such as direct band gap transition in low dimensional structures, strong light–matter interaction and good carrier mobility, combined with the possibility of fabricating thin MoS2 films, have attracted interest for this material in the field of optoelectronics. In this work, MoS2-based photodetectors are reviewed in terms of their main performance metrics, namely responsivity, detectivity, response time and dark current. Although neat MoS2-based detectors already show remarkable characteristics in the visible spectral range, MoS2 can be advantageously coupled with other materials to further improve the detector performance Nanoparticles (NPs) and quantum dots (QDs) have been exploited in combination with MoS2 to boost the response of the devices in the near ultraviolet (NUV) and infrared (IR) spectral range. Moreover, heterostructures with different materials (e.g., other TMDs, Graphene) can speed up the response of the photodetectors through the creation of built-in electric fields and the faster transport of charge carriers. Finally, in order to enhance the stability of the devices, perovskites have been exploited both as passivation layers and as electron reservoirs.

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Monte Carlo simulation study of detector performance for X-ray baggage inspection system

10.1063/5.0017839 ◽

2020 ◽

Author(s):

Amit Kumar ◽

Anita Topkar

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Simulation Study ◽

Inspection System ◽

Detector Performance ◽

Monte Carlo Simulation Study ◽

X Ray

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NDIR CO2 gas sensing using CMOS compatible MEMS ScAlN-based pyroelectric detector

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2021.130437 ◽

2021 ◽

pp. 130437

Author(s):

Doris Keh Ting Ng ◽

Chong Pei Ho ◽

Linfang Xu ◽

Weiguo Chen ◽

Yuan Hsing Fu ◽

...

Keyword(s):

Gas Sensing ◽

Pyroelectric Detector ◽

Co2 Gas ◽

Cmos Compatible

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Observing and controlling a Tamm plasmon at the interface with a metasurface

Nanophotonics ◽

10.1515/nanoph-2019-0514 ◽

2020 ◽

Vol 9 (4) ◽

pp. 897-903 ◽

Cited By ~ 4

Author(s):

Oleksandr Buchnev ◽

Alexandr Belosludtsev ◽

Victor Reshetnyak ◽

Dean R. Evans ◽

Vassili A. Fedotov

Keyword(s):

Liquid Crystal ◽

Metal Film ◽

Near Infrared ◽

Thin Metal Film ◽

Outer Side ◽

Spectral Position ◽

External Perturbations ◽

Dielectric Mirror ◽

Wavelength Scale ◽

Sub Wavelength

AbstractWe demonstrate experimentally that Tamm plasmons in the near infrared can be supported by a dielectric mirror interfaced with a metasurface, a discontinuous thin metal film periodically patterned on the sub-wavelength scale. More crucially, not only do Tamm plasmons survive the nanopatterning of the metal film but they also become sensitive to external perturbations as a result. In particular, by depositing a nematic liquid crystal on the outer side of the metasurface, we were able to red shift the spectral position of Tamm plasmon by 35 nm, while electrical switching of the liquid crystal enabled us to tune the wavelength of this notoriously inert excitation within a 10-nm range.

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