scholarly journals THz technology for vision systems

2014 ◽  
Vol 27 (1) ◽  
pp. 129-136 ◽  
Author(s):  
J. Trontelj ◽  
A. Sesek ◽  
A. Svigelj
Keyword(s):  
Room Temperature ◽  
New Technology ◽  
Electrical Engineering ◽  
Thz Radiation ◽  
Vision Systems ◽  
Current Application ◽  
Operating Range ◽  
Imaging Results ◽  
System Solution ◽  
Thz Sensor

d.o.o, Sempeter pri Gorici, Slovenija KW nema KR nema The THz radiation brings new technology challenges and new opportunities to overcome some of the current application obstacles. In the paper a portable THz system is presented operating at room temperature. The presented solution is robust and inexpensive, convenient for many applications. The THz sensor fabricated at the Faculty of Electrical Engineering in the Laboratory for Microelectronics is currently one of the best sensors in its frequency operating range. It reaches sensitivity up to 1000V/W and NEP down to 5pW/?Hz in vacuum. With the proposed system solution variety of application can be covered. Some imaging results captured with the proposed system at different stand-off distances are shown in the paper.

scholarly journals Photothermal, Photoelectric, and Photothermoelectric Effects in Bi-Sb Thin Films in the Terahertz Frequency Range at Room Temperature

Photonics ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 76
Author(s):  
Mikhail K. Khodzitsky ◽  
Petr S. Demchenko ◽  
Dmitry V. Zykov ◽  
Anton D. Zaitsev ◽  
Elena S. Makarova ◽  
...  
Keyword(s):  
Thin Films ◽  
Terahertz Radiation ◽  
Room Temperature ◽  
Voltage Drop ◽  
Radiation Detection ◽  
Radiation Detectors ◽  
Thz Radiation ◽  
Terahertz Frequency ◽  
Frequency Range ◽  
Terahertz Frequency Range

The terahertz frequency range is promising for solving various practically important problems. However, for the terahertz technology development, there is still a problem with the lack of affordable and effective terahertz devices. One of the main tasks is to search for new materials with high sensitivity to terahertz radiation at room temperature. Bi1−xSbx thin films with various Sb concentrations seem to be suitable for such conditions. In this paper, the terahertz radiation influence onto the properties of thermoelectric Bi1−xSbx 200 nm films was investigated for the first time. The films were obtained by means of thermal evaporation in vacuum. They were affected by terahertz radiation at the frequency of 0.14 terahertz (THz) in the presence of thermal gradient, electric field or without these influences. The temporal dependencies of photoconductivity, temperature difference and voltage drop were measured. The obtained data demonstrate the possibility for practical use of Bi1−xSbx thin films for THz radiation detection. The results of our work promote the usage of these thermoelectric materials, as well as THz radiation detectors based on them, in various areas of modern THz photonics.

NanoBond® Assembly – A Rapid, Room Temperature Soldering Process

2011 ◽  
Vol 2011 (1) ◽  
pp. 000521-000526
Author(s):  
Jacques Matteau
Keyword(s):  
Room Temperature ◽  
New Technology ◽  
Local Heat ◽  
Temperature Sensitive ◽  
Ignition Process ◽  
Light Emitting ◽  
Exothermic Reactions ◽  
Soldering Process ◽  
Order Of Magnitude ◽  
Reactive Foils

Indium Corporation of America has commercialized a new technology that will revolutionize how manufacturers join components using solder materials. (See Figure 1) The joining process is based on the use of reactive multilayer foils as local heat sources. The foils are a new class of nano-engineered materials, in which self-propagating exothermic reactions can be ignited at room temperature through an ignition process. By inserting a multilayer foil between two solder layers and two components, heat generated by the reaction in the foil melts the solder and consequently bonds are completed at room temperature in air, argon or vacuum in approximately one second. The resulting metallic joints exhibit thermal conductivities two orders of magnitude higher, and thermal resistivity’s an order of magnitude lower, than current commercial TIMs. The use of reactive foils as a local heat source eliminates the need for torches, furnaces, or lasers, speeds the soldering processes, and dramatically reduces the total heat that is needed. Thus, temperature-sensitive or small components can be joined without thermal damage or excessive heating. In addition, mismatches in thermal contraction on cooling can be avoided because components see very small increases in temperature. This is particularly beneficial for joining metals to ceramics. The fabrication and characterization of the reactive foils is described, and the value proposition for NanoBonding is presented. This presentation also shows the applicability of this platform technology to many areas of packaging including Thermal Interface Materials, microelectronics, optoelectronics, and Light Emitting Diodes (LEDs)

Organic Based Heat Stabilizers for PVC: A Safer and more Environmentally Friendly Alternatives

2015 ◽  
Vol 659 ◽  
pp. 321-326 ◽  
Author(s):  
Aran Asawakosinchai ◽  
Chanchra Jubsilp ◽  
Sarawut Rimdusit
Keyword(s):  
Room Temperature ◽  
New Technology ◽  
Environmentally Friendly ◽  
Mechanical Analysis ◽  
Pipe Production ◽  
Short Term ◽  
Zinc Compounds ◽  
Heat Stabilizer ◽  
Pvc Pipe ◽  
Potential Use

Organic based stabilizers have been considered as a new technology providing environmentally friendly heat stabilizer for PVC pipe production to substitute conventional lead stabilizer as well as calcium zinc stabilizer. In this research, PVC samples stabilized with 5 types of heat stabilizers i.e. 1) commercial lead stabilizer, 2) commercial calcium zinc stabilizer, 3) commercial organic based stabilizer (OBS), 4) 1,3-dimetyl-6-aminouracil (DAU) and 5) eugenol, were investigated. From dynamic mechanical analysis, storage modulus at room temperature of PVC stabilized with DAU was found to provide the highest value among those stabilizers. Glass transition temperature of the PVC stabilized with all types of heat stabilizers was determined to be approximately 99°C except the value of about 89°C in eugenol stabilized PVC. Furthermore, PVC stabilized with commercial lead, calcium zinc stabilizer and commercial OBS could be reprocessed up to at least 5 cycles. Whereas, PVC stabilized with DAU was found to be able to withstand the processing cycle up to 4 cycles. Additionally, PVC stabilized with DAU showed the most outstanding short term thermal stability and can maintain its original color for at least up to 4 processing cycles. Finally, repeated processing of PVC stabilized with each type of heat stabilizers showed negligible effect on mechanical properties for at least up to 3 processing cycles. From the above results, it is evident that DAU showed high potential use as a safe and effective organic based heat stabilizer for PVC to substitute traditional lead or calcium zinc compounds.

Room temperature generation of THz radiation in GaN quantum wells structures

2013 ◽  
Author(s):  
A. Penot ◽  
J. Torres ◽  
P. Nouvel ◽  
L. Varani ◽  
F. Teppe ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Room Temperature ◽  
Thz Radiation

scholarly journals From a gas thermometer to a terahertz matrix (a review)

2021 ◽  
Vol 9 (4) ◽  
pp. 337-346
Author(s):  
Igor Gibin ◽  
Peter Kotlyar
Keyword(s):  
Physical Properties ◽  
High Sensitivity ◽  
Thz Radiation ◽  
Detection Ability ◽  
Operating Range ◽  
Design Scheme ◽  
Wide Range ◽  
History Of ◽  
Extreme Sensitivity ◽  
Graphene Membranes

The history of the invention and development of the gas thermometer and the ap-pearance of optical-acoustic receivers (OAP) based on it, starting from the first works of Bell, Hayes, Golay, and up to the present time, are considered. The ad-vantages of the OAP, consisting in a constant and high sensitivity in a wide range of the spectrum and the highest detection ability among thermal receivers, are not-ed. The main characteristics of membranes – the main elements of OAP-are con-sidered, and the physical properties of graphene, as the most preferred material for membranes, are analyzed. Estimates have been made showing that the use of SLG graphene membranes makes it possible to create IR and THZ radiation re-ceivers with cells of the order of tens of microns with extremely high sensitivity. A new design scheme is proposed for uncooled matrix helium-graphene optical-acoustic receivers with theoretically extreme sensitivity and speed and an operating range extended to helium temperatures.

scholarly journals Enhanced terahertz detection of multigate graphene nanostructures

Nanophotonics ◽  
2022 ◽  
Vol 0 (0) ◽  
Author(s):  
Juan A. Delgado-Notario ◽  
Wojciech Knap ◽  
Vito Clericò ◽  
Juan Salvador-Sánchez ◽  
Jaime Calvo-Gallego ◽  
...  
Keyword(s):  
High Performance ◽  
Room Temperature ◽  
Thz Radiation ◽  
Electron Hole ◽  
Back Gate ◽  
Potential Barriers ◽  
Terahertz Detection ◽  
Wide Range ◽  
Order Of Magnitude ◽  
Effect Transistor

Abstract Terahertz (THz) waves have revealed a great potential for use in various fields and for a wide range of challenging applications. High-performance detectors are, however, vital for exploitation of THz technology. Graphene plasmonic THz detectors have proven to be promising optoelectronic devices, but improving their performance is still necessary. In this work, an asymmetric-dual-grating-gate graphene-terahertz-field-effect-transistor with a graphite back-gate was fabricated and characterized under illumination of 0.3 THz radiation in the temperature range from 4.5 K up to the room temperature. The device was fabricated as a sub-THz detector using a heterostructure of h-BN/Graphene/h-BN/Graphite to make a transistor with a double asymmetric-grating-top-gate and a continuous graphite back-gate. By biasing the metallic top-gates and the graphite back-gate, abrupt n+n (or p+p) or np (or pn) junctions with different potential barriers are formed along the graphene layer leading to enhancement of the THz rectified signal by about an order of magnitude. The plasmonic rectification for graphene containing np junctions is interpreted as due to the plasmonic electron-hole ratchet mechanism, whereas, for graphene with n+n junctions, rectification is attributed to the differential plasmonic drag effect. This work shows a new way of responsivity enhancement and paves the way towards new record performances of graphene THz nano-photodetectors.

scholarly journals Development of a New Essential Oil-Based Technology to Maintain Fruit Quality in Tomato

Horticulturae ◽  
2021 ◽  
Vol 7 (9) ◽  
pp. 303
Author(s):  
Luisa Fernanda Duque ◽  
María Victoria Amador ◽  
Miguel Guzmán ◽  
Carlos Asensio ◽  
Juan Luis Valenzuela
Keyword(s):  
Fruit Quality ◽  
Ethylene Production ◽  
Room Temperature ◽  
New Technology ◽  
Good Alternative ◽  
Quality Parameters ◽  
Soluble Solids ◽  
Main Experiment ◽  
Tomato Cultivar ◽  
Tomato Fruits

In this study, a new technology was tested for its efficacy in the conservation of tomato fruits. An initial experiment was conducted to determine the effects of eugenol on the main quality parameters of Raf tomato fruits; then, a main experiment was performed to test the effectiveness of the new technology. In both experiments, fruits of the tomato cultivar Raf at the mature green stage were used. The preliminary experiment demonstrated the effectiveness of eugenol in maintaining fruit quality during the postharvest life of the fruit. In the main experiment, the fruits were packed using a sachet filled with a mixture consisting of 10:1:1 clinoptilolite clay, ground clove buds, and activated charcoal. This mixture was evaluated against a commercial ethylene scavenger composed mainly of KMnO4-impregnated sepiolite. Three lots of fruits were used: One batch was considered as the control, where the fruits were not packed but kept in an open box at room temperature. The fruits in the other two batches were packed in 2 L PET containers with lids at a rate of three fruits per container, and a sachet of ground cloves and a commercial scavenger was added inside each container in each batch. The containers were kept at room temperature, and the following main quality parameters were analyzed: ethylene production rate, firmness, color, content of soluble solids, and pigments. The results showed that ground clove buds led to a reduction in ethylene production which was associated with a delay in maturation and could be a good alternative for use in the active fruit packaging of horticultural products.

Research on Bio-Leaching of Nickel-Bearing Tailings in Jilin, China

2017 ◽  
Vol 262 ◽  
pp. 177-180
Author(s):  
Xin Wang ◽  
Hong Ying Yang ◽  
Lin Lin Tong ◽  
Zhe Nan Jin ◽  
Su Xing Zhao
Keyword(s):  
Comparative Study ◽  
Room Temperature ◽  
New Technology ◽  
Acid Leaching ◽  
Environmentally Friendly ◽  
Pulp Density ◽  
Bacterial Leaching ◽  
Indigenous Bacteria ◽  
Acid Pool ◽  
Local Species

Gradually bio-metallurgy technology is becoming an irreplaceable new technology. The nickel-bearing tailings in Jilin, China contains Ni 0.13 %, Cu 0.03%, Co 0.01%, S 15.20%, Fe 6.30%. A comparative study of the HQ0211 bacteria, indigenous bacteria (after the domestication named ZXJE511 bacteria) and acid pool leaching revealed that the local species ore leaching was preferably the best way. At pH 2.0, room temperature (about 23°C), pulp density 20%,the Ni, Co and Cu leaching rates were 70.08%, 40% and 57.67 % , respectively ,after 38 days of bioleaching, proving the superiority of the bacterial leaching of Ni, Co, Cu from tailings. Biological leaching tailings solved the problem of the conventional methods which could not be addressed by acid leaching. This technology is environmentally friendly and can make maximum use of the resources, thereby avoiding the waste of the resources.

Negative conductivity of graphene with direct electric current

2021 ◽  
Author(s):  
I.M. Moiseenko ◽  
V.V. Popov ◽  
D.V. Fateev
Keyword(s):  
Reflection Coefficient ◽  
Electric Current ◽  
Terahertz Radiation ◽  
Room Temperature ◽  
Negative Real Part ◽  
Wave Incident ◽  
Thz Radiation ◽  
Direct Electric Current ◽  
Radiation Sources ◽  
Dc Current

Problem formulating. Currently, there are no compact, efficient terahertz radiation sources operating at room temperature. To create such sources and amplifiers, structures based on graphene with DC-current can be used. Goal. Finding conditions for achieving the negative real part of graphene conductivity and amplification of THz radiation in graphene with a direct electric current. Result. It is shown that for a certain value of direct electric current in graphene, the reflection coefficient of the THz wave incident on the structure based on graphene with DC-current exceeds unity, which indicates the amplification of THz radiation in the structure. The amplification of the THz radiation in graphene is achieved due to negative values of the real part of the graphene conductivity. Practical meaning. Results can be used to create sources and amplifiers of terahertz radiation.

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