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Archive for the ‘quantum physics’ category: Page 392

May 8, 2020

Scientists demonstrate quantum radar prototype

Posted by in categories: biotech/medical, quantum physics, security

Physicists at the Institute of Science and Technology Austria (IST Austria) have invented a new radar prototype that uses quantum entanglement as a method of object detection. This successful integration of quantum mechanics into devices could significantly impact the biomedical and security industries. The research is published in the journal Science Advances.

Quantum entanglement is a physical phenomenon whereby two particles remain interconnected, sharing physical traits regardless of how far apart they are from one another. Now, scientists from the research group of Professor Johannes Fink at the Institute of Science and Technology Austria (IST Austria) along with collaborators Stefano Pirandola from the Massachusetts Institute of Technology (MIT) and the University of York, UK, and David Vitali from the University of Camerino, Italy—have demonstrated a new type of detection technology called microwave quantum illumination that utilizes entangled as a method of detection. The prototype, which is also known as a quantum , is able to detect objects in noisy thermal environments where classical radar systems often fail. The technology has potential applications for ultra-low power biomedical imaging and security scanners.

May 8, 2020

Graphene Nanomesh: New Nanotechnology ‘Brick’ for Modern Micromachines

Posted by in categories: computing, engineering, nanotechnology, quantum physics

Researchers at Japan advanced institute of science and technology (JAIST) have successfully fabrication the suspended graphene nanomesh in a large area by the helium ion beam microscopy. 6nm diameter nanopores were pattern on the 1.2 um long and 500 nm wide suspended graphene uniformly. By systematically controlling the pitch (nanopore’s center to nanopore’s center) from 15 nm to 50 nm, a series of stable graphene nanomesh devices were achieved. This provides a practical way to investigate the intrinsic properties of graphene nanomesh towards the application for gas sensing, phonon engineering, and quantum technology.

Graphene, with its excellent electrical, thermal and optical properties, is promising for many applications in the next decade. It is also a potential candidate instead of silicon to build the next generation of electrical circuits. However, without a bandgap, it is not straightforward to use graphene as field-effect transistors (FETs). Researchers tried to cut the graphene sheet into a small piece of graphene nanoribbon and observed the bandgap opening successfully. However, the current of graphene nanoribbons is too low to drive the integrated circuit. In this case, the graphene nanomesh is pointed out by introducing periodical nanopores on the graphene, which is also considered as very small graphene nanoribbon array.

A research team led by Dr Fayong Liu and Professor Hiroshi MIZUTA has demonstrated in collaboration with researchers at the National Institute of Advanced Industrial Science and Technology (AIST) that large area suspended graphene nanomesh is quickly achievable by the helium ion beam microscopy with sub-10 nm nanopore diameter and well-controlled pitches. Comparing to slow speed TEM patterning, the helium ion beam milling technique overcomes the speed limitation, and meanwhile, provides a high imaging resolution. With the initial electrical measurements, it has found that the thermal activation energy of the graphene nanomesh increased exponentially by increasing the porosity of the graphene nanomesh. This immediately provides a new method for bandgap engineering beyond the conventional nanoribbon method. The team plans to continue exploring graphene nanomesh towards the application of phonon engineering.

May 8, 2020

Scientists publish data on COVID-19-related proteins

Posted by in categories: chemistry, quantum physics

A group of scientists led by Teruki Honma of the RIKEN Center for Biosystems Dynamics Research and including collaborators from Hoshi University and Mizuho Information & Research Institute have released key data on the proteins associated with the novel coronavirus that causes COVID-19. As a means to facilitate the development of anti-COVID-19 therapeutics, crystal structures of dozens of drug targets including the virus’s main protease, RNA dependent RNA polymerase, and S protein have been published by Protein Data Bank (PDB). The research group has performed ab initio quantum chemical calculations based on the crystal structures using the fragment molecule orbital method, and published the data at FMODB as a database for data acquired using that method. According Honma, “We hope that this data will help scientists quickly develop therapies for this devastating virus. We will continue to perform FMO calculations on newly released protein structures and update our data. This data will be important by allowing an understanding of the precise energy data for interactions between drug candidates and virus proteins.”

The data is available at FMODB: The database of quantum mechanical data based on the FMO methodThe webpage will open in a new tab..

May 7, 2020

Quantum resonances near absolute zero

Posted by in categories: chemistry, energy, quantum physics

Recently, Prof. Yang Xueming from the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences and Prof. Yang Tiangang from the Southern University of Science and Technology discussed significant advances in the study of quantum resonances in atomic and molecular collisions at near absolute zero temperature. Their article was published in Science on May 7.

The rules of quantum mechanics govern all atomic and molecular processes. Understanding the quantum nature of atomic and is essential for understanding energy transfer and chemical reaction processes, especially in the low collisional energy region, where quantum effect is the most prominent.

A remarkable feature of quantum nature in atomic and molecular collision is quantum scattering resonances, but probing them experimentally has been a great challenge due to the transient nature of these resonances.

May 7, 2020

Laser loop couples quantum systems over a distance

Posted by in categories: biotech/medical, computing, nanotechnology, quantum physics

For the first time, researchers have succeeded in creating strong coupling between quantum systems over a great distance. They accomplished this with a novel method in which a laser loop connects the systems, enabling nearly lossless exchange of information and strong interaction between them. In the journal Science, physicists from the University of Basel and University of Hanover reported that the new method opens up new possibilities in quantum networks and quantum sensor technology.

Quantum technology is currently one of the most active fields of research worldwide. It takes advantage of the special properties of quantum mechanical states of atoms, light, or nanostructures to develop, for example, novel sensors for medicine and navigation, networks for information processing and powerful simulators for materials sciences. Generating these quantum states normally requires a between the systems involved, such as between several atoms or nanostructures.

Until now, however, sufficiently strong interactions were limited to short distances. Typically, two systems had to be placed close to each other on the same chip at low temperatures or in the same vacuum chamber, where they interact via electrostatic or magnetostatic forces. Coupling them across larger distances, however, is required for many applications such as or certain types of sensors.

May 7, 2020

Degenerate Quantum Gases (BEC, DFG)

Posted by in categories: particle physics, quantum physics

Einstein bose condensate can make ultra powerful lasers. bigsmile


The general understanding of nature involves three, sometimes four states of matter. We all are well aware of solids, liquids and gases, plus – if we think about stars – plasmas. The state in which a specific “matter” is found depends on the relation between interaction energy and temperature. In 1924, a revolutionary article was published by Bose and Einstein theoretically describing that particles should undergo a phase transition at low temperatures even if there is no or negligible interaction between them. This phase transition would not rely on an interaction between the particles but occur only due to quantum statistical effects relying on the indistinguishable nature of particles with integer spin (called bosons). This was a striking prediction and it took 71 years until this phase transition could clearly be observed in dilute atomic gases by three research groups in 1995. Only 6 years later, the Nobel Prize in physics was awarded to E. A. Cornell, W. Ketterle and C. E. Wieman “for the achievement of Bose-Einstein condensation in dilute gases of alkali atoms, and for early fundamental studies of the properties of the condensates”. The headline was simpler: “New state of matter revealed: Bose-Einstein condensate”. This was just a beginning of a still exploding research field. Not only are Bose-Einstein condensate the coldest things in universe – temperatures below one nK (1 billionth of a K above absolute zero) have been observed, they also show unique properties, e.g. behave as one giant matter wave. Weakly interacting particles with half integer spin (Fermions) do not undergo a phase transition to a Bose-Einstein condensate (BEC). Still one can cool them so far that quantum statistical effects dominate. The system is called degenerate Fermi gas (DFG) and again strange behavior occurs. Both types of degenerate quantum gases, BEC and DFG, are investigated in optical lattices to study solid state physics. New methods for precise tuning of the atomic interaction were used to study effects of High-Tc super conductivity, to create molecular BECs or to investigate dipolar BECs.

Formation of Bose-Einstein condensates

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May 7, 2020

Long-lived pionic helium: Exotic matter experimentally verified for the first time

Posted by in categories: chemistry, particle physics, quantum physics

Exotic atoms in which electrons are replaced by other subatomic particles of the same charge allow deep insights into the quantum world. After eight years of ongoing research, a group led by Masaki Hori, senior physicist at the Max Planck Institute of Quantum Optics in Garching, Germany, has now succeeded in a challenging experiment: In a helium atom, they replaced an electron with a pion in a specific quantum state and verified the existence of this long-lived “pionic helium” for the very first time. The usually short-lived pion could thereby exist 1000 times longer than it normally would in other varieties of matter. Pions belong to an important family of particles that determine the stability and decay of atomic nuclei. The pionic helium atom enables scientists to study pions in an extremely precise manner using laser spectroscopy. The research is published in this week’s edition of Nature.

For eight years, the group worked on this challenging experiment, which has the potential to establish a new field of research. The team experimentally demonstrated for the first time that long-lived pionic really exist. “It is a form of chemical reaction that happens automatically,” explains Hori. The exotic atom was first theoretically predicted in 1964 after experiments at that time pointed toward its existence. However, it was considered extremely difficult to verify this prediction experimentally. Usually, in an atom, the extremely short-lived decays quickly. However, in pionic helium, it can be conserved in a sense so it lives 1000 times longer than it normally does in other atoms.

May 7, 2020

Powerful new magnet provides fresh insight into ‘frozen’ quantum materials

Posted by in categories: particle physics, quantum physics

Researchers at the Department of Energy’s (DOE’s) Oak Ridge National Laboratory (ORNL) have finished the preliminary commissioning of a new 14-tesla magnet at the Spallation Neutron Source (SNS). This new sample environment allows researchers to explore the fundamental physics behind complex behavior of quantum matter.

The magnet, which also features an optional dilution refrigerator insert, is the latest low-temperature sample to be commissioned at SNS. Weighing 2,670 pounds and standing nearly 7 feet tall, this massive device is an excellent tool for researchers wanting to learn more about materials that exhibit quantum phenomena. Its powerful magnetic field forces quantum particles to behave in an orderly way, giving scientists the opportunity to locate patterns in otherwise disordered . And with its refrigerator—which can chill samples to −459.65° F—scientists can essentially “freeze” molecular vibrations in materials that might appear as background noise in neutron scattering studies. This allows for more accurate measurements of the excitations associated with quantum magnets.

“Quantum systems often lack discernible order. This makes it difficult to understand their fundamental characteristics. This new sample environment lets us bring order to these systems we’re interested in studying,” said Matt Stone, a lead instrument scientist at ORNL.

May 7, 2020

Intro to Quantum Computing

Posted by in categories: computing, encryption, quantum physics

Quantum computing is seen by many as a technology of the future. In this article, we’re going to look at how to run some non-trivial programs on actual quantum computers. In particular, we’re going to discuss something called graph states. Graph states are used for quantum cryptography, quantum error correction, and measurement based quantum computing. If all of that sounds like a foreign language, that’s okay. We’re going to go through everything, from the ground up, and in detail…and don’t worry, we’ll keep it light and fun.

May 7, 2020

A Discovery That Long Eluded Physicists: Superconductivity to the Edge

Posted by in categories: computing, quantum physics

Princeton researchers detect a supercurrent a current flowing without energy loss at the edge of a superconductor with a topological twist.

A discovery that long eluded physicists has been detected in a laboratory at Princeton. A team of physicists detected superconducting currents — the flow of electrons without wasting energy — along the exterior edge of a superconducting material. The finding was published May 1 in the journal Science.

The superconductor that the researchers studied is also a topological semi-metal, a material that comes with its own unusual electronic properties. The finding suggests ways to unlock a new era of “topological superconductivity” that could have value for quantum computing.