Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Micromechanical Bolometers for Subterahertz Detection at Room Temperature.

ABSTRACT: Fast room-temperature imaging at terahertz (THz) and subterahertz (sub-THz) frequencies is an interesting technique that could unleash the full potential of plenty of applications in security, healthcare, and industrial production. In this Letter, we introduce micromechanical bolometers based on silicon nitride trampoline membranes as broad-range detectors down to sub-THz frequencies. They show, at the longest wavelengths, room-temperature noise-equivalent powers comparable to those of state-of-the-art commercial devices (∼100 pW Hz^-1/2), which, along with the good operation speed and the easy, large-scale fabrication process, could make the trampoline membrane the next candidate for cheap room-temperature THz imaging and related applications.

SUBMITTER: Vicarelli L

PROVIDER: S-EPMC8855436 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Micromechanical Bolometers for Subterahertz Detection at Room Temperature.

Vicarelli Leonardo L Tredicucci Alessandro A Pitanti Alessandro A

ACS photonics 20220128 2

Fast room-temperature imaging at terahertz (THz) and subterahertz (sub-THz) frequencies is an interesting technique that could unleash the full potential of plenty of applications in security, healthcare, and industrial production. In this Letter, we introduce micromechanical bolometers based on silicon nitride trampoline membranes as broad-range detectors down to sub-THz frequencies. They show, at the longest wavelengths, room-temperature noise-equivalent powers comparable to those of state-of- ...[more]

PMID: 35211645

Similar Datasets

Graphene-based mid-infrared room-temperature pyroelectric bolometers with ultrahigh temperature coefficient of resistance.

Project description:There is a growing number of applications demanding highly sensitive photodetectors in the mid-infrared. Thermal photodetectors, such as bolometers, have emerged as the technology of choice, because they do not need cooling. The performance of a bolometer is linked to its temperature coefficient of resistance (TCR, ∼2-4% K-1 for state-of-the-art materials). Graphene is ideally suited for optoelectronic applications, with a variety of reported photodetectors ranging from visible to THz frequencies. For the mid-infrared, graphene-based detectors with TCRs ∼4-11% K-1 have been demonstrated. Here we present an uncooled, mid-infrared photodetector, where the pyroelectric response of a LiNbO3 crystal is transduced with high gain (up to 200) into resistivity modulation for graphene. This is achieved by fabricating a floating metallic structure that concentrates the pyroelectric charge on the top-gate capacitor of the graphene channel, leading to TCRs up to 900% K-1, and the ability to resolve temperature variations down to 15 μK.

| S-EPMC5290316 | biostudies-literature

Performance Comparison of SOI-Based Temperature Sensors for Room-Temperature Terahertz Antenna-Coupled Bolometers: MOSFET, PN Junction Diode and Resistor.

Project description:Assuming that the 0.6-?m silicon-on-insulator (SOI) complementary metal-oxide-semiconductor (CMOS) technology, different Si-based temperature sensors such as metal-oxide-semiconductor field-effect transistor (MOSFET) (n-channel and p-channel), pn-junction diode (with p-body doping and without doping), and resistors (n+ or p+ single crystalline Si and n+ polycrystalline Si) were designed and characterized for its possible use in 1-THz antenna-coupled bolometers. The use of a half-wave dipole antenna connected to the heater end was assumed, which limited the integrated temperature sensor/heater area to be 15 × 15 µm. Our main focus was to evaluate the performances of the temperature sensor/heater part, and the optical coupling between the incident light and heater via an antenna was not included in the evaluation. The electrothermal feedback (ETF) effect due to the bias current was considered in the performance estimation. A comparative analysis of various SOI bolometers revealed the largest responsivity (Rv) of 5.16 kV/W for the n-channel MOSFET bolometer although the negative ETF in MOSFET reduced the Rv. The noise measurement of the n-channel MOSFET showed the NEP of 245 pW/Hz1/2, which was more than one order of magnitude smaller than that of the n+ polycrystalline Si resistive bolometer (6.59 nW/Hz1/2). The present result suggests that the n-channel MOSFET can be a promising detector for THz applications.

| S-EPMC7464105 | biostudies-literature

Ultrasensitive photoelectric detection with room temperature extremum.

Project description:Room-temperature photodetection holds pivotal significance in diverse applications such as sensing, imaging, telecommunications, and environmental remote sensing due to its simplicity, versatility, and indispensability. Although different kinds of photon and thermal detectors have been realized, high sensitivity of photodetection with room temperature extremum is not reported until now. Herein, we find evident peaks in the photoelectric response originated from the anomalous excitonic insulator phase transition in tantalum nickel selenide (Ta2NiSe5) for room-temperature optimized photodetection from visible light to terahertz ranges. Extreme sensitivity of photoconductive detector with specific detectivity (D*) of 5.3 × 1011 cm·Hz1/2·W-1 and electrical bandwidth of 360 kHz is reached in the terahertz range, which is one to two orders of magnitude improvement compared to that of the state-of-the-art room-temperature terahertz detectors. The van der Waals heterostructure of Ta2NiSe5/WS2 is further constructed to suppress the dark current at room temperature with much improved ambient D* of 4.1 × 1012 cm·Hz1/2·W-1 in the visible wavelength, rivaling that of the typical photodetectors, and superior photoelectric performance in the terahertz range compared to the photoconductor device. Our results open a new avenue for optoelectronics via excitonic insulator phase transition in broad wavelength bands and pave the way for applications in sensitive environmental and remote sensing at room temperature.

| S-EPMC11861971 | biostudies-literature

Lmo0688 (GmaR) regulon at room temperature

Project description:Microarray analyses comparing the transcriptional profile of wild-type EGDe relative to ∆lmo0688 (L. monocytogenes) during standing growth at RT in BHI broth. These analyses revealed that Lmo0688 is required for expression of flagellar motility genes during growth at RT. In this study, we identify an additional component of the molecular circuitry governing temperature-dependent flagellar gene expression. At low temperatures (30˚C and below), MogR repression activity is specifically inhibited by an anti-repressor, GmaR. We demonstrate that GmaR forms a stable complex with MogR, preventing MogR from binding its DNA target sites. GmaR anti-repression activity is temperature-dependent due to DegU-dependent transcriptional activation of gmaR at low temperatures. Thus, GmaR production represents the first committed step for flagella production in L. monocytogenes. Interestingly, GmaR also functions as a glycosyltransferase exhibiting O-linked N-acetylglucosamine transferase (OGT) activity for flagellin (FlaA). GmaR is the first OGT to be identified and characterized in prokaryotes. Unlike the well-characterized, highly conserved OGT regulatory protein in eukaryotes, the catalytic activity of GmaR is functionally separable from its anti-repression function. Keywords: EGDe vs ∆688, Temperature, Growth condition

2006-10-31 | GSE6032 | GEO

Room-temperature-storable PCR mixes for SARS-CoV-2 detection.

Project description:ObjectivesA novel coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) emerged in late 2019, causing an outbreak of pneumonia [coronavirus disease 2019 (COVID-19)] globally. Although the use of ready-made reaction mixes can enable more rapid PCR-based diagnosis of COVID-19, the need to transport and store these mixes at low temperatures presents challenges to already overburdened logistics networks.MethodsHere, we present an optimized freeze-drying procedure that allows SARS-CoV-2 PCR mixes to be transported and stored at ambient temperatures, without loss of activity. Additive-supplemented PCR mixes were freeze-dried. The residual moisture of the freeze-dried PCR mixes was measured by Karl-Fischer titration.ResultsWe found that the freeze-dried PCR mixes with ~1.2% residual moisture are optimal for storage, transport, and reconstitution. The sensitivity, specificity, and repeatability of the freeze-dried reagents were similar to those of freshly prepared, wet reagents. The freeze-dried mixes retained activity at room temperature (18 ~ 25 °C) for 28 days, and for 14 and 10 days when stored at 37 °C and 56 °C, respectively.ConclusionThe uptake of this approach will ease logistical challenges faced by transport networks and make more cold storage space available at diagnosis and hospital laboratories.

| S-EPMC7313492 | biostudies-literature

Warm Water Versus Room Temperature Water Immersion Colonoscopy

Project description:Water immersion insertion has been documented to decrease procedure-related discomfort during colonoscopy. There was used warm water infusion for colonoscope insertion in most of the water immersion colonoscopy trials. The investigators have been using room temperature water (20-24°C) for water immersion and the investigators did not notice any drawback of it. In our opinion, it is simpler and cheaper option for water immersion colonoscopy and proof of its efficacy and safety could support the use of water immersion technique in routine practice. The primary endpoint is cecal intubation time and the investigators suppose that the use of warm water infusion does not shorten it significantly. Patient comfort during colonoscope insertion, water consumption, length of the scope while reaching the cecum, need for external compression, need for positioning of the patient and endoscopist´s difficulty with colonoscopy will be also assessed.

| 2124104 | ecrin-mdr-crc

Near-Room-Temperature Ethanol Detection Using Ag-Loaded Mesoporous Carbon Nitrides.

Project description:Development of room-temperature gas sensors is a much sought-after aspect that has fostered research in realizing new two-dimensional materials with high surface area for rapid response and low-ppm detection of volatile organic compounds (VOCs). Herein, a fast-response and low-ppm ethanol gas sensor operating at near room temperature has been fabricated successfully by utilizing cubic mesoporous graphitic carbon nitride (g-CN, commonly known as g-C3N4), synthesized through template inversion of mesoporous silica, KIT-6. Upon exposure to 50 ppm ethanol at 250 °C, the optimized Ag/g-CN showed a significantly higher response (R a/R g = 49.2), fast response (11.5 s), and full recovery within 7 s in air. Results of sensing tests conducted at 40 °C show that the sensor exhibits not only a highly selective response to 50 ppm (R a/R g = 1.3) and 100 ppm (R a/R g = 3.2) of ethanol gas but also highly reversible and rapid response and recovery along with long-term stability. This outstanding response is due to its easily accessible three-dimensional mesoporous structure with higher surface area and unique planar morphology of Ag/g-CN. This study could provide new avenues for the design of next-generation room-temperature VOC sensors for effective and efficient monitoring of alarming concern over indoor environment.

| S-EPMC6641218 | biostudies-literature

Anisotropic ultrasensitive PdTe2-based phototransistor for room-temperature long-wavelength detection.

Project description:Emergent topological Dirac semimetals afford fresh pathways for optoelectronics, although device implementation has been elusive to date. Specifically, palladium ditelluride (PdTe2) combines the capabilities provided by its peculiar band structure, with topologically protected electronic states, with advantages related to the occurrence of high-mobility charge carriers and ambient stability. Here, we demonstrate large photogalvanic effects with high anisotropy at terahertz frequency in PdTe2-based devices. A responsivity of 10 A/W and a noise-equivalent power lower than 2 pW/Hz0.5 are achieved at room temperature, validating the suitability of PdTe2-based devices for applications in photosensing, polarization-sensitive detection, and large-area fast imaging. Our findings open opportunities for exploring uncooled and sensitive photoelectronic devices based on topological semimetals, especially in the highly pursuit terahertz band.

| S-EPMC7467699 | biostudies-literature

CdS nanodroplets over silica microballs for efficient room-temperature LPG detection.

Project description:An efficient room-temperature sensor for liquified petroleum gas (LPG) is demonstrated by employing CdS:SiO2 nanocomposite thin films (CdS:SiO2 NCTFs) for the first time. CdS:SiO2 NCTFs exhibiting the morphology of CdS nanodroplets on micron-sized spherical balls of SiO2 were deposited using the pulsed laser deposition (PLD) method, followed by thermal annealing. The targets of chemically synthesized CdS nanoparticles and commercially procured SiO2 were used to deposit CdS:SiO2 NCTFs by swapping them at a frequency ratio of 2 : 8 laser pulses per second, which was selected to ensure nearly the same ratio of CdS to SiO2 in NCTFs and was confirmed by X-ray photoelectron spectroscopy. Sensor fabrication was carried out on bare CdS thin films and as-grown and annealed CdS:SiO2 NCTFs using an Ag paste over Pt interdigitated electrodes to measure the resistance of the films in air and in the presence of reducing gases, viz., LPG, H2, H2S, NO2 and CO2. The present sensor showed the highest response for LPG and the observed value was ∼71% for 1000 ppm at RT with the response time and recovery time of 91 s and 140 s, respectively. The response of the sensor was sustainable up to 75 °C and then decreased, which suggested its promising usage for low-temperature regions as well. A low detection limit of 20 ppm at RT for LPG was determined; however, a significant response was observed only at 50 ppm. The sensor retained ∼96% of its initial response even after 8 weeks and that too at 100 °C. The present LPG sensor is highly promising due to its high sensitivity, low detection limit, low response and recovery times, good reproducibility, RT operation and simple fabrication technique.

| S-EPMC9418948 | biostudies-literature

Ultra-sensitive heterodyne detection at room temperature in the atmospheric windows.

Project description:We report room temperature heterodyne detection of a quantum cascade laser beaten with a local oscillator on a unipolar quantum photodetector in two different atmospheric windows, at 4.8 µm and 9 µm. A noise equivalent power of few pW is measured by employing an active stabilization technique in which the local oscillator and the signal are locked in phase. The measured heterodyne noise equivalent power is six orders of magnitude lower than that obtained with direct detection.

| S-EPMC11501748 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data