Photonics Spectra: electrons This is the syndication feed for Photonics Spectra: electrons. https://www.photonics.com/Splash.aspx?Tag=electrons Fri, 29 Mar 2024 01:23:52 GMT Tue, 03 Oct 2023 09:58:06 GMT 1800 Agostini, Krausz, L’Huillier Earn Nobel Prize in Physics for Work on Attosecond Pulses
Pierre Agostini, Ferenc Krausz, and Anne L’Huillier have been awarded the 2023 Nobel Prize in physics for experimental methods that generate attosecond pulses of light for the study of electron dynamics in matter. The work of the laureates has developed and enabled new tools to explore the movement of electronics inside atoms and molecules, movement that occurs at extremely short timescales. Agostini, Krausz, and L'Huillier were awarded 11 million SEK ($989,495) to be shared equally.
Anne L'Huillier, professor of atomic physics at Lund University. Courtesy of Niklas Elmehed, Nobel Prize Outreach. In 1987, L’Huillier and her colleagues at the Commissariat à l’Energie Atomique in Saclay, France, fired short...]]>
https://www.photonics.com/Articles/Agostini_Krausz_LHuillier_Earn_Nobel_Prize_in/p5/a69369 A69369 Tue, 03 Oct 2023 09:58:06 GMT
Doping Process Increases Conductivity, Transparency of Graphene
An interdisciplinary team of researchers from Columbia University and Sungkyungkwan University (South Korea) has introduced a clean technique to dope graphene via a charge-transfer layer made of low-impurity tungsten oxyselenide (TOS).

The team generated the new “clean” layer by oxidizing a single atomic layer of another 2D material, tungsten selenide. When team members layered TOS on top of the graphene, they found that it left the graphene riddled with electricity-conducting holes. The holes could be fine-tuned to better control the materials’ electricity-conducting properties by adding a few atomic layers of tungsten selenide between the TOS and graphene.

The researchers found that graphene’s...]]>
https://www.photonics.com/Articles/Doping_Process_Increases_Conductivity/p5/a67506 A67506 Mon, 08 Nov 2021 07:00:00 GMT
Shaping Light-Activated Nanocatalysts
A comparative study from Rice University researchers in the college’s Laboratory for Nanophotonics (LANP) demonstrated how the shape of nanoparticles affects their ability to drive light-activated reactions. The work is part of LANP’s ongoing green chemistry initiative to develop commercially viable, light-activated nanocatalysts that can insert energy into chemical reactions with surgical precision.

The researchers studied differently shaped, but otherwise identical, aluminum nanoparticles, the most rounded of which had 14 sides and 24 blunt points. The second was cube shaped with six sides and eight 90° corners. The last, which the team dubbed “octopod,” also had six sides, but each of its eight corners...]]>
https://www.photonics.com/Articles/Shaping_Light-Activated_Nanocatalysts/p5/a66202 A66202 Fri, 25 Sep 2020 07:00:00 GMT
Research Team Develops High-Power Device that Helps Create Nanoplasma
The team at the Power and Wide-band-gap Electronics Research Laboratory (POWERlab), led by Elison Matioli, built a nanodevice that enables the generation of extremely high-power signals in just a few picoseconds, producing high-power THz waves. The EPFL researchers say they are hoping to mitigate the costs and materials demand of traditional THz waves.

The researchers say the high-power picosecond operation of these devices may help with some advanced medical treatment techniques such as...]]>
https://www.photonics.com/Articles/Research_Team_Develops_High-Power_Device_that/p5/a65717 A65717 Tue, 14 Apr 2020 07:00:00 GMT
Quantum Interference Observed Using UV-Light Spectroscopy
Various chemical reactions, such as the breaking of bonds in molecules, are triggered by the absorption of light. In the first moment after the absorption, the distribution of the electrons in the atomic shell changes, significantly influencing the...]]>
https://www.photonics.com/Articles/Quantum_Interference_Observed_Using_UV-Light/p5/a65558 A65558 Wed, 19 Feb 2020 08:00:00 GMT
Researchers Build Chip-Size Particle Accelerator
For the first time, scientists at Stanford University and the SLAC National Accelerator Laboratory have created a silicon chip that can accelerate electrons using an infrared laser to deliver, at less than a hair’s width, the sort of energy boost that takes microwaves several feet.

Until now, the university scientists have relied on a two-mile-long accelerator to deliver electrons through a vacuum pipe. Bursts of microwave radiation launch the electrons at a velocity just shy of the speed of light. The product of this electron projection is a beam powerful enough to help scientists around the world probe the atomic and molecular structures of both organic and inorganic materials.

Writing in the Jan. 3 issue of Science, a...]]>
https://www.photonics.com/Articles/Researchers_Build_Chip-Size_Particle_Accelerator/p5/a65417 A65417 Thu, 02 Jan 2020 14:00:00 GMT
Researchers Develop Sub-Femtosecond Transportation for Electrons
The task for the research team was to develop an experimental setup for manipulating ultrashort light pulses at femtosecond scales below a single oscillation cycle while creating nanostructures suited for high-precision measurements and manipulation of electronic...]]>
https://www.photonics.com/Articles/Researchers_Develop_Sub-Femtosecond/p5/a65411 A65411 Fri, 27 Dec 2019 12:24:01 GMT
Ultrafast Optics Faces Challenges Outside of Research Labs
Ultrafast optics is currently a scientifically dominated area with a lot of dynamics in both research and development. Often, complex setups make it challenging to create compact devices that can be employed for applications outside of the laboratory or in medical environments.

But stepping toward commercial approaches goes hand in hand with the development of industry-proven fiber lasers, as well as multifunctional and multimodal microscopy technologies.

Doctoral students adjust the pump laser of a high-repetition rate optical parametric chirped pulse amplifier (OPCPA) at the Munich-Centre for Advanced Photonics (MAP). Courtesy of Thorsten Naeser/Max Planck Institute for Quantum Optics.
Today, ultrashort laser pulses with...]]>
https://www.photonics.com/Articles/Ultrafast_Optics_Faces_Challenges_Outside_of/p5/a62238 A62238 Mon, 10 Jul 2017 15:08:18 GMT
Photons and Electrons Produce Hybrid Light-Matter Fluid
Light is composed of waves, but it can also behave like a liquid. In certain circumstances it can ripple and spiral around obstacles. These liquid properties of light emerge when the photons that form the light wave interact with each other.

The flow of polaritons encounters an obstacle in the supersonic (top) and superfluid (bottom) regime. Courtesy of Polytechnique Montreal.
Researchers from Polytechnique Montreal and CNR Nanotec in Lecce, Italy have shown that combining light with electrons emits an even more dramatic effect. Researcher Daniele Sanvitto said the light can become a superfluid with frictionless flow across and around an obstacle without any ripples.

“Superfluidity is an impressive effect, normally...]]>
https://www.photonics.com/Articles/Photons_and_Electrons_Produce_Hybrid_Light-Matter/p5/a62129 A62129 Fri, 09 Jun 2017 14:37:13 GMT
Lighting, Displays and More Go Organic
That glowing screen in the palm of your hand might foretell the future. It’s not some new app, but the screen itself. OLEDs — organic light-emitting diodes — have muscled their way into mobile applications and are now found on many devices.

“You’ve got something like 400 to 500 million displays, at least, that have been manufactured to date worldwide,” said Mike Hack. “So it’s been very successful in mobile.”

Hack is a vice president at Universal Display Corp. of Ewing, N.J. The company invents and develops phosphorescent OLED technologies and materials for the display and lighting industries.

Devices and films that absorb light and emit electrons, the reverse of...]]>
https://www.photonics.com/Articles/Lighting_Displays_and_More_Go_Organic/p5/a57682 A57682 Tue, 01 Sep 2015 13:05:26 GMT
Graphene Phenomenon Could Enable New Lasers
Understanding the dynamics of electrons in graphene under strong magnetic fields could lead to development of new types of broadband lasers.

An international team led by Helmholtz-Zentrum Dresden-Rossendorf (HZDR) exposed graphene to a 4-Tesla magnetic field, which forced electrons in the material into certain energy states called Landau levels.

These energy levels were then examined with a free-electron laser.

Electron redistribution through Auger scattering has been discovered in graphene. Courtesy of Voigt/HZDR.

“The laser pulse excites the electrons into a certain Landau level. A temporally delayed pulse then probes how the system evolves,” said doctoral candidate Martin Mittendorff. The researchers...]]>
https://www.photonics.com/Articles/Graphene_Phenomenon_Could_Enable_New_Lasers/p5/a56935 A56935 Tue, 25 Nov 2014 00:00:00 GMT
Lasers Used to Generate Electron Spin Currents
Ultrashort laser pulses are being used to advance research into electron spin currents, a potential field for next-generation data storage.

Electron spin, or angular momentum, is typically random and therefore produces no spin current, which is key to operating spintronic devices. Spin currents can be driven by differences in voltage across a structure, but two separate studies show this is not necessarily the only — or even the most efficient — method.

Ultrafast laser light creates heat transport through a ferromagnet, producing an electron spin current. Courtesy of Gyung-Min Choi/University of Illinois at Urbana-Champaign.

Researchers at University of Illinois at Urbana-Champaign found that spin current can...]]>
https://www.photonics.com/Articles/Lasers_Used_to_Generate_Electron_Spin_Currents/p5/a56435 A56435 Fri, 11 Jul 2014 00:00:00 GMT
Researchers Probe Inner Workings of Solar Panels
Using femtosecond stimulated Raman spectroscopy (SRS), scientists now understand the inner workings of plastic solar panels.

A team from the University of Montreal, in conjunction with England’s Science and Technology Facilities Council, Imperial College London and the University of Cyprus, says the findings could further efforts to improve solar panels and broaden their use.

“Our findings are of key importance for a fundamental mechanistic understanding, with molecular detail, of all solar conversion systems,” said Françoise Provencher, a doctoral candidate at the University of Montreal.

Three laser beams are needed to record excited vibrational modes in solar panels using femtosecond stimulated...]]>
https://www.photonics.com/Articles/Researchers_Probe_Inner_Workings_of_Solar_Panels/p5/a56413 A56413 Thu, 03 Jul 2014 00:00:00 GMT
New Class of Nanoparticles Could Herald Flexible Solar Cells
A team from the Edward S. Rogers Sr. Department of Electrical and Computer Engineering at the University of Toronto — in collaboration with Dalhousie University, King Abdullah University of Science and Technology and Huazhong University of Science and Technology — has designed a class of solar-sensitive nanoparticles that they say outperforms traditional solar cells.

Called colloidal quantum dots, the new solid, stable nanoparticles could allow for more flexible solar cells, as well as better gas sensors, infrared lasers and infrared light emitting diodes.

Tiny colloidal quantum dots used to collect sunlight...]]>
https://www.photonics.com/Articles/New_Class_of_Nanoparticles_Could_Herald_Flexible/p5/a56315 A56315 Tue, 10 Jun 2014 00:00:00 GMT
Nanostructures Show Promise for Efficient LEDs
Nanostructures and an indium nitride (InN) semiconductor could hold promise for improving the efficiency of LEDs, particularly in the green gap, where productivity typically takes a dive.

Researchers from the University of Michigan conducted tests at the US Department of Energy's National Energy Research Scientific Computing Center using the Cray XC30 supercomputer. They discovered that the semiconductor, which traditionally emits IR radiation, can also emit green light when reduced to 1-nm-wide wires.

A 1-nm-wide indium nitride wire shows the distribution of an electron around a positively charged hole. Strong quantum confinement in these small nanostructures enables efficient light emission at visible wavelengths. Courtesy of...]]>
https://www.photonics.com/Articles/Nanostructures_Show_Promise_for_Efficient_LEDs/p5/a56052 A56052 Tue, 08 Apr 2014 00:00:00 GMT
Combining Technologies Creates Ultrathin Light Detectors
A first-ever combination of technologies has resulted in the creation of an extremely thin light detector.

By integrating metamaterials and quantum cascade structures, a team from the Vienna University of Technology has coupled light into the ultrathin systems of semiconductor layers that comprise the devices, a task that has proved difficult in past studies.

The semiconductor layers can turn electrical voltage into light, and they can also serve as light detectors. With the new technique, the researchers use metamaterials whose specific microscopic structure can manipulate light in the terahertz range.

The metamaterial couples the incident light to the semiconductor. It can then be converted into an electric signal....]]>
https://www.photonics.com/Articles/Combining_Technologies_Creates_Ultrathin_Light/p5/a56006 A56006 Fri, 28 Mar 2014 00:00:00 GMT
Shrink Wrapping Disease Biomarkers
A new technique for better detection of infectious disease biomarkers has scientists looking at ordinary shrink wrap in a whole new way.

Developed by a team at the University of California, Irvine, the method uses shrink wrap coated with a combination of metals to boost the signal of fluorescent markers used in biosensing a thousandfold. The technique could enable earlier detection of infectious diseases and more effective treatment.

In their study, the researchers deposited thin layers of gold and nickel onto a thermoplastic polymer. When heated, the shrink wrap contracts and causes the stiffer metal layers to buckle and wrinkle into flowerlike structures that are much smaller than those previously demonstrated.

Shrink...]]>
https://www.photonics.com/Articles/Shrink_Wrapping_Disease_Biomarkers/p5/a55987 A55987 Fri, 21 Mar 2014 00:00:00 GMT
Tech Breakthrough with Nanoscale Optical Switch
The new device, developed by a team from Vanderbilt University, the University of Alabama at Birmingham and Los Alamos National Laboratory, is now the smallest of the existing ultrafast optical switches, representing a major breakthrough in light-detecting electronic technology.

Containing individual switches measuring only 200 nm in diameter, this new optical device can turn on and off trillions of times per second. It is made of a metamaterial consisting of nanoscale particles of vanadium dioxide that are deposited on a glass substrate and coated...]]>
https://www.photonics.com/Articles/Tech_Breakthrough_with_Nanoscale_Optical_Switch/p5/a55972 A55972 Tue, 18 Mar 2014 00:00:00 GMT
Small 2-D Material Has Big Potential
Although small and just a few atoms thick, a new material has big possibilities for the field of optoelectronics.

A 2-D material called tungsten diselenide (WSe2), which could potentially manipulate light and electricity interactions, has already demonstrated improved efficiency and spectral properties in a variety of applications, including lighting, displays, optical interconnects, logics and sensors.

Researchers from MIT say this novel material could also lead to the creation of ultrathin, lightweight, flexible photovoltaic cells, enhanced LEDs and other optoelectronic devices.

Researchers supplied electricity to a small piece of tungsten selenide through two gold wires, causing it to emit light and demonstrate its...]]>
https://www.photonics.com/Articles/Small_2-D_Material_Has_Big_Potential/p5/a55966 A55966 Fri, 14 Mar 2014 00:00:00 GMT
Quantum Droplets Form in Laser-Shot Semiconductors
The accidental discovery of a new quasiparticle that behaves like a drop of liquid could provide a better understanding of solid-state devices such as semiconductors and superconductors.

Scientists at the University of Colorado made the discovery during extremely low-temperature semiconductor and laser experiments. Described as a quantum droplet, scientists are calling the quasiparticle a dropleton. It has properties unlike anything seen before, they said.

Researchers in Colorado have discovered a new quasiparticle that can offer better understanding of solid-state devices. Images courtesy of University of Colorado.
The research team cooled a gallium-arsenide semiconductor to –263 °C and shot it with ultrafast laser...]]>
https://www.photonics.com/Articles/Quantum_Droplets_Form_in_Laser-Shot_Semiconductors/p5/a55902 A55902 Mon, 03 Mar 2014 00:00:00 GMT