#High-temperature superconductivity in atomically thin films: A route to developing ultimate superconducting nanodevices A research group at Tohoku University has succeeded in fabricating an atomically thin,
high-temperature superconductor film with a superconducting transition temperature (Tc) of up to 60 K(-213°C). The team, led by Prof.
Takashi Takahashi (WPI-AIMR) and Asst. Prof. Kosuke Nakayama (Dept. of Physics), also established the method to control/tune the Tc.
This finding not only provides an ideal platform for investigating the mechanism of superconductivity in the two-dimensional system,
but also paves the way for the development of next-generation nanoscale superconducting devices. The research results were published in Nature Materials on June 1
2015. Superconductors are regarded as one of the most promising candidates for next-generation advanced electronic devices,
because the unique quantum effects in superconductors are a great advantage in achieving the energy saving
and ultrahigh-speed processing. However, the device application of superconductors has long been hindered. The largest obstacle is the necessity of a huge and expensive cooling system with liquid helium, because of the low Tc of conventional superconductors,
which is close to absolute zero (0 K, -273°C)* 1. It has also been a big challenge to realize the high-density integration of superconductors into electronic devices.
In order to overcome these problems it is definitely necessary to develop a new superconductor with higher-Tc,
that can be fabricated into a thin film. The research team at Tohoku University turned its attention to iron selenide (Fese),
which is a member of iron-based superconductors*2 . While the Tc of bulk Fese is only 8 K(-265°C a signature of higher-Tc superconductivity has been suggested in ultrathin film
and its verification has been required urgently. The researchers at first fabricated high-quality, atomically thin Fese films Fig. 1, with thickness of between one monolayer (which corresponds to three-atoms thickness) and twenty monolayers (sixty-atoms thickness
by using the molecular-beam-epitaxy (MBE) method*3. Then they carefully investigated the electronic structure of grown films by angle-resolved photoemission spectroscopy (ARPES)* 4 Fig. 2. In the ARPES measurement,
the researchers observed the opening of a superconducting gap at low temperature*5, which is direct evidence of the emergence of superconductivity in the films.
The researchers found that the Tc estimated from the gap-closing in a monolayer film is surprisingly high (above 60 K),
which is about 8 times higher than the Tc of bulk Fese. While multilayer films do not show superconductivity in the as-grown state
the researchers have discovered a novel method to deposit alkali atoms onto the films and thereby control the electron density in the film.
By employing this method, the researchers have succeeded in converting non-superconducting multilayer Fese films into high-Tc superconductors with Tc as high as 50 K. The present result gives a great impact to both the basic
and applied researches in superconductors. The researchers have shown clearly how the superconductivity is emerged, enhanced and controlled in atomically thin Fese films.
While the Tc achieved in this study (50-60 K) is still lower than that of the cuprate high-Tc superconductors (highest Tc?
135 K) which caused the"high-Tc fever"in the world 30 years ago, it obviously exceeds the record of other"high-Tc superconductors"such as fullerene (C60) superconductors (Tc 33 K) and Mgb2 (Tc 39k),
closely approaching the temperature of liquid nitrogen (77 K). The present report would lead to intensive researches to further increase Tc by changing the number of atomic layers, the amount of doped electrons and the species of substrate.
The present result would also widen the range of both basic and applied researches on superconductivity,
because the Tc of 50-60 K achieved in the present study is high enough to keep the superconducting state by using a closed-cycle-gas-type cooling system without liquid helium.
The present success in fabricating an atomically thin high-temperature superconductor not only provides an ideal platform to investigate the novel two-dimensional superconductivity,
but also opens a route to developing an ultimate superconducting nanodevice consisting of atomic-size electronic parts.
The ultrathin high-Tc superconductor would effectively contribute to the significant downsizing and consequent high-density integration in electric circuits,
leading to the realization of future-generation electronic devices with high energy-saving and ultrahigh-speed operation.
This work was supported by grants from the Japan Society for the Promotion of Science (JSPS) and Japan's Ministry of Education
Culture, Sports, Science and Technology (MEXT) E
#Leti Demos New Process to Fabricate High-brightness Micro-LED Arrays for Next-gen Head-mounted and Head up displays:
Gallium nitride (Gan) and Indium Gallium nitride (Ingan) Technology Targets Fast-growing Markets for Wearable Vision Systems Abstract:
CEA-Leti today announced that it has demonstrated a path to fabricating high-density micro-LED arrays for the next generation of wearable and nomadic systems in a process that is scalable to the IC manufacturing process.
The high-brightness, enhanced-vision systems such as head up and head-mounted displays can improve safety and performance in fields such as aeronautics and automotive,
where the displays allow pilots and drivers to receive key navigation data and information in their line of sight.
For consumers, smart glasses or nomadic projection devices with augmented reality provide directions, safety updates advertisements and other information across the viewing field.
LED microdisplays are suited ideally for such wearable systems because of their low footprint, low power consumption, high-contrast ratio and ultra-high brightness.
Leti researchers have developed gallium nitride (Gan) and indium gallium nitride (Ingan) LED TECHNOLOGY for producing high-brightness, emissive microdisplays for these uses,
which are expected to grow dramatically in the next three to five years. For example, the global research firm Marketsandmarkets forecasts the market for head up displays alone to grow from $1. 37 billion in 2012 to $8. 36 billion in 2020. urrently available microdisplays for both head-mounted
and compact head up applications suffer from fundamental technology limitations that prevent the design of very low-weight,
compact and low energy-use products, said Ludovic Poupinet, head of Leti Optics and Photonics Department. eti technology breakthrough is the first demonstration of a high-brightness,
high-density micro-LED array that overcomes these limitations and is scalable to a standard microelectronic large-scale process.
This technology provides a low-cost, leading-edge solution to companies that want to target the fast-growth markets for wearable vision systems.
Announced during Display Week 2015 in San jose, Calif, . Leti technology innovation IS LED based on micro arrays that are hybridized on a silicon backplane.
and 3d heterogeneous integration of such LED arrays on CMOS active-matrices. These innovations make it possible to produce a brightness of 1 million cd/m for monochrome devices
and 100 kcd/m for full-color devices with a device size below one inch and 2. 5 million pixels.
#An inexpensive rival to graphene aerogels: Researchers in China have created a new 3-dimensional polypyrrole aerogel-based electromagnetic absorber material that can serve as an inexpensive alternative to costly graphene aerogels Abstract:
The electromagnetic radiation discharged by electronic equipment and devices is known to hinder their smooth operation. Conventional materials used today to shield from incoming electromagnetic waves tend to be sheets of metal or composites,
which rely on reflection as a shielding mechanism. But now, materials such as graphene aerogels are gaining traction as more desirable alternatives
because they act as electromagnetic absorbers. They're widely expected to improve energy storage, sensors, nanoelectronics, catalysis and separations,
but graphene aerogels are prohibitively expensive and difficult to produce for large-scale applications because of the complicated purification
and functionalization steps involved in their fabrication. So a team of researchers in China set out to design a cheaper material with properties similar to a graphene aerogel--in terms of its conductivity,
as well as a lightweight, anticorrosive, porous structure. In the journal Applied Physics Letters, from AIP Publishing, the researchers describe the new material they created and its performance.
Aming Xie, an expert in organic chemistry, and Fan Wu, both affiliated with PLA University of Science and Technology, worked with colleagues at Nanjing University of Science
and Technology to tap into organic chemistry and conducting polymers to fabricate a three-dimensional (3-D) polypyrrole (PPY) aerogel-based electromagnetic absorber.
They chose to concentrate on this method because it enables them to"regulate the density and dielectric property of conducting polymers through the formation of pores during the oxidation polymerization of the pyrrole monomer,"
"explained Wu. And the fabrication process is a simple one.""It requires only four common chemical reagents:
pyrrole, ferric chloride (Fecl3), ethanol and water--which makes it cheap enough and enables large-scale fabrication,
"We're also able to pour the Fecl3 solution directly into the pyrrole solution--not drop by drop--to force the pyrrole to polymerize into a 3-D aerogel rather than PPY particles."
"In short, the team's 3-D PPY aerogel is designed to exhibit"desirable properties such as a porous structure and low density,"Wu noted.
Compared with previous works, the team's new aerogel has the lowest adjunction and widest effective bandwidth--with a reflection loss below-10 decibels.
In terms of applications, based on the combination of low adjunction and a"wide"effective bandwidth, the researchers expect to see their 3-D PPY aerogel used in surface coatings for aircraft.
Another potential application is as coatings within the realm of corrosion prevention and control.""Common anticorrosion coatings contain a large amount of zinc (70 to 80 percent by weight),
and these particles not only serve as a cathode by corroding to protect the iron structure
but also to maintain a suitable conductivity for the electrochemistry process, "Wu pointed out.""If our 3-D PPY aerogel could build a conductivity network in this type of coating,
the loss of zinc particles could be reduced rapidly.""The team is now taking their work a step further by pursuing a 3-D PPY/PEDOT-based (poly (3, 4-ethylenedioxythiophene) electromagnetic absorber."
"Our goal is to grow solid-state polymerized PEDOT particles in the holes of the 3-D PPY aerogel formed by PPY chains,"Wu added d
#World's smallest spirals could guard against identity theft Abstract: Take gold spirals about the size of a dime...
if they were added to identity cards, currency and other important objects. Students and faculty at Vanderbilt University fabricated these tiny Archimedes'spirals and then used ultrafast lasers at Vanderbilt and the Pacific Northwest National Laboratory in Richland,
Washington to characterize their optical properties. The results are reported in a paper published online by the Journal of Nanophotonics on May 21."
the Vanderbilt doctoral student who figured out how to study their optical behavior. The spirals were designed
and made at Vanderbilt by another doctoral student, Jed Ziegler, now at the Naval Research Laboratory.
Most other investigators who have studied the remarkable properties of microscopic spirals have done so by arranging discrete nanoparticles in a spiral pattern:
A number of crystals produce this effect, called frequency doubling or harmonic generation, to various degrees.
The strongest frequency doubler previously known is the synthetic crystal beta barium borate, but the nano-spirals produce four times more blue light per unit volume.
When infrared laser light strikes the tiny spirals it is absorbed by electrons in the gold arms.
Electrons that are driven toward the center absorb enough energy so that some of them emit blue light at double the frequency of the incoming infrared light."
"said Stevenson Professor of Physics Richard Haglund, who directed the research.""If you bow a violin string very lightly it produces a single tone.
The electrons at the center of the spirals are driven pretty vigorously by the laser's electric field.
Because of the tiny quantities of metal actually used they can be made inexpensively out of precious metals,
which resist chemical degradation. They can also be made on plastic, paper and a number of other substrates."
"If nano-spirals were embedded in a credit card or identification card, they could be detected by a device comparable to a barcode reader,
The device would be capable of measuring the temperature of a cell's interior Researchers from the UAB and the University of Nottingham,
"finding a nanothermometer sensitive enough at this scale is a great step forward in the field of nanotechnology, with applications in biology, chemistry, physics and even in the diagnosis and treatment of diseases
stretchable ceramics made by flame technology Abstract: Scientists at Kiel University have successfully been able to transfer the experience from furnace to laboratory
while synthesizing nanoscale materials using simple and highly efficient flame technology. This baking of nanostructures has already been a great success using zinc oxide.
The recent findings concentrate on tin oxide, which opens up a wide field of possible new applications.
The material scientists published their latest research data in todays issue (Friday, 5 june) of the renowned scientific journal Advanced Electronic Materials.
Synthesizing nanoscale materials takes place within high-tech laboratories, where scientists in full-body suits keep every grain of dust away from their sensitive innovations.
However scientists at Kiel University proved that this is not always necessary. They have successfully been able to transfer the experience from furnace to laboratory
while synthesizing nanoscale materials using simple and highly efficient flame technology. This baking of nanostructures has already been a great success using zinc oxide.
The recent findings concentrate on tin oxide, which opens up a wide field of possible new applications.
The material scientists published their latest research data in todays issue (Friday, 5 june) of the renowned scientific journal Advanced Electronic Materials.
Metal oxides in bulk form are generally brittle, which limits their desired utilizations. Their one-dimensional (1d) structures
such as belt-like nanostructures, exhibit much more application potential because of their high surface to volume ratio.
However, 1d nanostructures are still difficult to use, because integrating them in real devices is a challenging task.
we have developed three-dimensional (3d) macroscopic material from 1d tin oxide belt-like nanostructures. The resulting ceramic networks exhibit most of the nanoscale properties,
including flexibility. It can therefore be utilized freely for any desired application. We are pleased very that our recently introduced flame transport synthesis method on the basis of zinc oxide now enables the simple synthesis of interconnected 3d networks from tin oxide
says Dr Yogendra Kumar Mishra, group leader of the working group Functional Nanomaterials at Kiel University,
and main author of the study. The fascinating part is the structure of the single belt-like nanostructures delivered by this synthesis on the basis of tin oxide crystal structure.
In contrast to ceramic produced with zinc oxide, which leads to very short tetrapod structures, tin oxide gives long, flat structures.
They are just like fettucine, compares Professor Rainer Adelung, Chairperson of the Functional Nanomaterials group.
And these long flat noodles grow together in a very specific way: In the oven used for the synthesis, temperatures stay just below the melting point of tin oxide.
Thus, the noodles find specific interconnection points by kinetics instead of thermodynamics. Each junction is forced into a well-defined angle following strict geometric principles,
adds Professor Lorenz Kienle, Chairperson of the Synthesis and Real Structure group. The structural design of the tin oxide 3d network, meaning the grown-together noodles, was investigated in detail using transmission electron microscopy.
Further potential applications could also be flexible and stretchable electronic devices, luminescent actuators, batteries, smart cloths or sacrificial templates for the growth of new materials.
This work has been performed in co-operation with Professor Ion Tiginyanu and his team members from the Technical University of Moldova
Development of such 3d network materials from tin oxide, with geometry determining defects made by flame transport synthesis at Kiel University is a very interesting step forward into the future of nanostructure growth and applications."#
This is what Kiel University's research focus"Kiel Nano, Surface and Interface Science"(Kinsis) is busy investigating.
In Kinsis, material scientists, chemists, physicists, biologists, electrical engineers, information scientists, food scientists and physicians work closely together.
Molecular machines, novel sensors, bionic materials, quantum computers, advanced therapies and much more can emerge from this endeavour.
'internet: www. uni-kiel. de, Jubilee: www. uni-kiel. de/cau350twitter: www. twitter. com/kieluni, Facebook:
www. facebook. com/kielunicopyright Alphagalileoissuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
Bookmark: Full bibliographic information News and information Next-generation illumination using silicon quantum dot-based white-blue LED June 7th,
2015uab researchers design the most precise quantum thermometer to date: The device would be capable of measuring the temperature of a cell's interior June 7th, 2015ceramic Nanomembrane, New Material for Dehydration of Natural gas June 7th,
2015tappi Announces 2015 Nanotechnology Division Technical Award Winner June 6th, 2015discoveries Next-generation illumination using silicon quantum dot-based white-blue LED June 7th,
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/Metamaterials Ceramic Nanomembrane, New Material for Dehydration of Natural gas June 7th, 2015tappi Announces 2015 Nanotechnology Division Technical Award Winner June 6th, 2015unlocking nanofibers potential:
Prototype boosts production of versatile fibers fourfold, while cutting energy consumption by 92 percent June 5th, 2015tenasitech secures additional $509,
000 funding to bring scratch resistant acrylics to the world June 5th, 2015announcements Next-generation illumination using silicon quantum dot-based white-blue LED June 7th,
2015uab researchers design the most precise quantum thermometer to date: The device would be capable of measuring the temperature of a cell's interior June 7th, 2015ceramic Nanomembrane, New Material for Dehydration of Natural gas June 7th,
2015tappi Announces 2015 Nanotechnology Division Technical Award Winner June 6th, 2015interviews/Book reviews/Essays/Reports/Podcasts/Journals/White papers Next-generation illumination using silicon quantum dot-based white-blue LED June 7th,
2015uab researchers design the most precise quantum thermometer to date: The device would be capable of measuring the temperature of a cell's interior June 7th, 2015ceramic Nanomembrane, New Material for Dehydration of Natural gas June 7th, 2015moving sector walls on the nano scale June 6th,
2015research partnerships Nature of Halogen Bonds Determined by Atomic Force Microscope June 2nd, 2015leti Demos New Process to Fabricate High-brightness Micro-LED Arrays for Next-gen Head-mounted and Head up displays:
Gallium nitride (Gan) and Indium Gallium nitride (Ingan) Technology Targets Fast-growing Markets for Wearable Vision Systems June 2nd, 2015a major advance in mastering the extraordinary properties of an emerging semiconductor:
Black phosphorus reveals its secrets thanks to a scientific breakthrough made by a team from Universite de Montreal, Polytechnique Montreal and CNRS in France June 2nd, 2015new heterogeneous wavelength tunable laser diode for high-frequency
efficiency June 2nd, 201 0
#Diffusion and Remote Detection of Hot-Carriers in Graphene Abstract: In a new article published in Nano Letters,
ICN2 researchers led by ICREA Prof Sergio O. Valenzuela have investigated hot carrier propagation across graphene using an electrical nonlocal injection/detection method.
The results create new opportunities for nanoscale bolometry and calorimetry and could have a strong impact in the performance of conventional graphene devices.
Due to the weak electron-phonon coupling in graphene, 2d Dirac massless carriers can present a much more elevated temperature than the graphene lattice.
Such hot carriers propagate over long distances resulting in novel thermoelectric and optoelectronic phenomena. Researchers of the ICN2 have studied such hot carrier propagation
and detection in a new article published in Nano Letters entitled Hot-Carrier Seebeck Effect:
Diffusion and Remote Detection of Hot-Carriers in Graphene. The research, led by ICREA Prof Sergio O. Valenzuela, Group Leader of the Physics and Engineering of Nanodevices Group and Dr. Juan F. Sierra,
Juan de la Cierva postdoctoral researcher, is focused on hot-carrier propagation across monolayer graphene using a novel electrical method in a device with multiple metal leads.
Hot carriers are generated locally by an electrical current, diffuse away from the injection point and are detected electrically in a remote voltage probe by measuring the thermoelectric voltage.
The relationship between the voltage and the dissipated Joule power in the injector is studied then.
At high temperatures the voltage is proportional to the power, as in ordinary thermoelectric experiments using an external heater.
which is demonstrated to represent a fingerprint of hot-carrier dominated thermoelectricity. The measurement scheme allows researchers to evaluate the characteristic cooling length for hot-carriers,
creates new opportunities for nanoscale bolometry and calorimetry.#####For more information, please click herecontacts: Alicia Labianwriteemail('icn. cat','alicia. labian';
'Copyright ICN2ISSUERS of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
stretchable ceramics made by flame technology June 7th, 2015ceramic Nanomembrane, New Material for Dehydration of Natural gas June 7th,
2015graphene Haydale Subsidiary Changes Name & Creates New Aerospace Unit June 4th, 2015environmental Issues to Hamper Growth of Global Nanocomposites Market June 4th, 2015an inexpensive rival
to graphene aerogels: Researchers in China have created a new 3-dimensional polypyrrole aerogel-based electromagnetic absorber material that can serve as an inexpensive alternative to costly graphene aerogels June 3rd,
2015central Florida Company Garmor Achieves Graphene Production Milestone: Garmor Inc, Increases Capacity for Manufacturing Graphene oxide at Customer Sites June 2nd, 2015chip Technology Moving sector walls on the nano scale June 6th, 2015fei Launches New
Dualbeam Plasma Focused Ion beam for Electrical Fault Isolation & Failure Analysis: New Helios PFIB EFI is integrated a fully deprocessing
and fault isolation solution that reduces analysis time from days to just hours June 4th, 2015production of Nanocomposites by Using Direct Nano-Welding of Micromaterials in Iran June 4th, 2015environmental Issues to Hamper Growth of Global Nanocomposites Market June 4th, 2015optical computing/Photonic computing New
heterogeneous wavelength tunable laser diode for high-frequency efficiency June 2nd, 2015entangled photons unlock new supersensitive characterisation of quantum technology June 1st, 2015stanford breakthrough heralds super-efficient light-based computers:
Light can transmit more data while consuming far less power than electricity, and an engineering feat brings optical data transport closer to replacing wires May 29th,
2015dna Double Helix Does Double Duty in Assembling Arrays of Nanoparticles: Synthetic pieces of biological molecule form framework and glue for making nanoparticle clusters and arrays May 25th, 2015discoveries Tissue Engineering Scaffolds Produced from Natural Silk in Iran June 8th,
2015uab researchers design the most precise quantum thermometer to date: The device would be capable of measuring the temperature of a cell's interior June 7th,
2015tin follows zinc: stretchable ceramics made by flame technology June 7th, 2015ceramic Nanomembrane, New Material for Dehydration of Natural gas June 7th,
2015announcements Tissue Engineering Scaffolds Produced from Natural Silk in Iran June 8th, 2015uab researchers design the most precise quantum thermometer to date:
The device would be capable of measuring the temperature of a cell's interior June 7th,
stretchable ceramics made by flame technology June 7th, 2015ceramic Nanomembrane, New Material for Dehydration of Natural gas June 7th,
2015next-generation illumination using silicon quantum dot-based white-blue LED June 7th, 2015uab researchers design the most precise quantum thermometer to date:
stretchable ceramics made by flame technology June 7th, 2015battery Technology/Capacitors/Generators/Piezoelectrics/Thermoelectrics/Energy storage Researchers synthesize magnetic nanoparticles that could offer alternative to Rare earth magnets June 1st,
2015trees are source for high-capacity, soft batteries May 31st, 2015new'designer carbon'from Stanford boosts battery performance May 30th,
2015chemists discover key reaction mechanism behind the highly touted sodium-oxygen battery May 28th, 2015photonics/Optics/Lasers A major advance in mastering the extraordinary properties of an emerging semiconductor:
Black phosphorus reveals its secrets thanks to a scientific breakthrough made by a team from Universite de Montreal, Polytechnique Montreal and CNRS in France June 2nd, 2015new heterogeneous wavelength tunable laser diode for high-frequency efficiency June 2nd,
2015entangled photons unlock new supersensitive characterisation of quantum technology June 1st, 2015ucf Research and Innovation Recognized at International Conference May 31st,201 0
Iranian researchers produced biocompatible and biodegradable nanocomposite scaffolds by using a type of natural silk with no cellular toxicity observed in the experiments.
Silk fibroin is a natural polymer produced by various insects. This substance has applications in the production of tissue engineering scaffolds as a biological material due to its appropriate mechanical properties and computability.
It can also be used in the production of artificial skin or other medical stuff. In this research, nanocomposite scaffold was made of silk fibroin,
chitosan and alumina through freeze drying method. The produced scaffold has a homogenous structure with pore sizes of 135-148 micrometers."
"The size of pores decreases due to the presence of alumina ceramic nanoparticles in the synthesis of the nanocomposite scaffold.
In addition, when alumin ceramic is added to the polymeric bed, the mechanical properties of the scaffold increases and desirable biocompatibility properties are obtained.
Therefore, the proposed nanocomposite scaffold is appropriate from the amount and porosity distribution points of view for the growth of gum fibroblast cells,"Dr. Abbas Teimouri, one of the researchers, stated.
According to the researcher, the mechanical strength, degradability, water sorption and inorganic bioactivity of the produced nanocomposite scaffold have been evaluated by carrying out various tests
including MTT and liquid movement porosimetry. Based on the results, the interaction between the organic and inorganic phases increases mechanical properties and water sorption of silk fibroin/chitosan/alumina scaffold.
In addition, no sign of toxicity has been observed at the laboratorial scale. Results of the research have been published in RSC Advances,
vol. 5, issue 35,2015, pp. 27558-27570.#####For more information, please click herecopyright Fars News Agencyissuers of news releases, not 7th Wave,
Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content. Bookmark: News and information Diffusion and Remote Detection of Hot-Carriers in Graphene June 8th, 2015uab researchers design the most precise quantum thermometer to date:
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