Researchers from NIST and California Institute of Technology (Caltech) have demonstrated a new design for an atomic clock that is based on a chip-scale frequency comb, or a microcomb. The microcomb clock, featured in Optica, is the first demonstration of all-optical control of the microcomb, and its accurate conversion of optical frequencies to lower microwave frequencies.
Spinach gave Popeye super strength, but it also holds the promise of a different power for a group of scientists: the ability to convert sunlight into a clean, efficient alternative fuel. Purdue Univ. physicists are part of an international group using spinach to study the proteins involved in photosynthesis, the process by which plants convert the sun’s energy into carbohydrates used to power cellular processes.
A team of Dartmouth scientists and their colleagues have devised a breakthrough laser that uses a single artificial atom to generate and emit particles of light—and may play a crucial role in the development of quantum computers, which are predicted to eventually outperform even today’s most powerful supercomputers.
Empty space is a bubbling soup of various virtual particles popping in and out of existence. Theorists from Austria and Vienna have recently proposed a way to amplify the force of these counter-intuitive phenomena called “vacuum fluctuations” by several orders of magnitude using a transmission line, channelling virtual photons. The strategy could have profound implications for understanding Casimir and Van der Waals forces.
Researchers in Spain have announced their successful effort to build a silicon 1-D optomechanical crystal so that it allows both phonons and photons to localize in a stable way. This marks an opportunity to study the interaction between electromagnetic radiation and mechanical vibrations of matter with a new level of precision.
Graphene, a material that consists of a lattice of carbon atoms, one atom thick, is widely touted as being the most electrically conductive material ever studied. However, not all graphene is the same. With so few atoms comprising the entirety of the material, the arrangement of each one has an impact on its overall function.
Applying just the right amount of tension to a chain of carbon atoms can turn it from a metallic conductor to an insulator, according to Rice Univ. scientists. Stretching the material known as carbyne by just 3% can begin to change its properties in ways that engineers might find useful for mechanically activated nanoscale electronics and optics.
Using two thin, tiny gold nanorods 10,000 times thinner than a human hair, researchers from the U.S. and Germany have succeeded in creating an adjustable filter for so-called circularly polarized light. This switch for nano-optics is made from two tiny gold rods that reversibly change their optical properties when specific DNA molecules are added.
Lawrence Livermore National Laboratory scientists for the first time have experimentally re-created the conditions that exist deep inside giant planets, such as Jupiter, Uranus and many of the planets recently discovered outside our solar system. Researchers can now re-create and accurately measure material properties that control how these planets evolve over time, information essential for understanding how these massive objects form.
Ultra-fast x-ray laser research led by Kansas State Univ. has provided scientists with a snapshot of a fundamental molecular phenomenon. The finding sheds new light on microscopic electron motion in molecules. The researchers measured at which distances between the two atoms the electron transfer can occur.
One of the major road blocks to the design and development of new, more efficient solar cells may have been cleared. Researchers with the Lawrence Berkeley National Laboratory have developed the first ab initio method for characterizing the properties of “hot carriers” in semiconductors. Hot carriers are electrical charge carriers with significantly higher energy than charge carriers at thermal equilibrium.
Biological physicists at Rice Univ. have succeeded in analyzing transmembrane protein folding in the same way they study the proteins’ free-floating, globular cousins. They have applied energy landscape theory to proteins that are hard to view because they are inside cell membranes. The method should increase the technique’s value to researchers who study proteins implicated in diseases and possibly in the creation of drugs to treat them.
A heat-sensing camera designed at Arizona State University has provided data to create the most detailed global map yet made of Martian surface properties. THEMIS, the nine-band visual and infrared camera on NASA’s Mars Odyssey orbiter, was used to create this map, which is now available online. And citizen scientists are invited to help make it even better.
One of the great, unanswered questions for space weather scientists is just what creates two gigantic donuts of radiation surrounding Earth, called the Van Allen radiation belts. Theories abound, but probes sent by NASA have recently provided the first really strong confirmation of what's happening. For the first time, scientists can explain how the electrons are accelerated up to nearly the speed of light.
Scientists in Texas have created a unique sensor that amplifies the optical signature of molecules by about 100 billion times. The new imaging method uses a form of Raman spectroscopy in combination with an intricate but mass reproducible optical amplifier. Newly published tests found the device could accurately identify the composition and structure of individual molecules containing fewer than 20 atoms.
Using a newly developed, ultrafast femtosecond infrared light source, chemists at the University of Chicago have been able to directly visualize the coordinated vibrations between hydrogen-bonded molecules. This marks the first time this sort of chemical interaction, which is found in nature everywhere at the molecular level, has been directly visualized.
Researchers at RIKEN in Japan, in collaboration with researchers from Purdue Univ., have recently demonstrated the scalability of quantum dot architectures by trapping and controlling four electrons in a single device. Circuits based on quantum dots are one of the most promising practical routes to harnessing the potential of quantum computing.
Scientists running the ATLAS experiment at the Large Hadron Collider report the first evidence of a process that can be used to test the mechanism by which the recently discovered Higgs particle imparts mass to other fundamental particles. More rare than the production of the Higgs itself, this process also provides a new stringent test of the Standard Model of particle physics.
Lithium-ion batteries could benefit from a theoretical model created at Rice Univ. and Lawrence Livermore National Laboratory that predicts how carbon components will perform as electrodes. The model is based on intrinsic electronic characteristics of materials used as battery anodes. These include the material’s quantum capacitance and the material’s absolute Fermi level.
Last year, Massachusetts Institute of Technology researchers discovered that when water droplets spontaneously jump away from superhydrophobic surfaces during condensation, they can gain electric charge in the process. Now, the same team has demonstrated that this process can generate small amounts of electricity that might be used to power electronic devices.
A research team in Illinois has built a new type of tunable nanoscale antenna that could facilitate optomechanical systems that actuate mechanical motion through plasmonic field enhancements. The team’s fabrication process shows for the first time an innovative way of fabricating plasmonic nanoantenna structures under a scanning electron microscope, which avoids complications from conventional lithography techniques.
Scientists in Israel have recently constructed, for the first time, a photonic router that enables routing of single photons by single photons. At the core of the device is an atom that can switch between two states. The state is set just by sending a single particle of light, or photon, from the right or the left via an optical fiber. The innovation could help overcome difficulties in building quantum computers.
Biophysics researchers have used short pulses of light to peer into the mechanics of photosynthesis and illuminate the role that molecule vibrations play in the energy conversion process that powers life on our planet. The findings could potentially help engineers make more efficient solar cells and energy storage systems.
Spin current, in which an ultra-short laser pulse generates electrons all with the same spin, is a promising new technology which potentially allows data to be stored 1,000 times as fast as traditional hard drive. Researchers in The Netherlands have recently shown that generated spin current is actually able to cause a change in magnetization, hinting at practical application in the future.
Too cool and faint, many objects in the universe are impossible to detect with visible light. Now a Northwestern Univ. team has refined a new technology that could make these colder objects more visible, paving the way for enhanced exploration of deep space. The new technology uses a type II superlattice material called indium arsenide/indium arsenide antimonide (InAs/InAsSb).