PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

First observation of spin Hall effect in a quantum gas is step toward 'atomtronics'

2013-06-06
(Press-News.org) Researchers at the National Institute of Standards and Technology (NIST) have reported* the first observation of the "spin Hall effect" in a Bose-Einstein condensate (BEC), a cloud of ultracold atoms acting as a single quantum object. As one consequence, they made the atoms, which spin like a child's top, skew to one side or the other, by an amount dependent on the spin direction. Besides offering new insight into the quantum mechanical world, they say the phenomenon is a step toward applications in "atomtronics"—the use of ultracold atoms as circuit components.

The spin Hall effect is seen in electrons and other quantum particles when their motion depends on their magnetic orientation, or "spin." Previously, the spin Hall effect has been observed in electrons confined to a two-dimensional semiconductor strip, and in photons, but never before in a BEC.

A quantum circuit might use spins, described as "up" or "down," as signals, in a way analogous to how electric charge can represent ones and zeros in conventional computers. Quantum devices, however, can process information in ways that are difficult or impossible for conventional devices. Finding ways to manipulate spin is a major research effort among quantum scientists, and the team's results may help the spin Hall effect become a good tool for the job.

The team used several sets of lasers to trap rubidium atoms in a tiny cloud, about 10 micrometers on a side, inside a vacuum chamber and then cool the atoms to a few billionths of a degree above absolute zero. Under these conditions, the atoms change from an ordinary gas to an exotic state of matter called a BEC, in which the atoms all behave identically. Then, the NIST team employed another laser to gently push the BEC, allowing them to observe the spin Hall effect at work.

Spin is roughly analogous to the rotation of a top, and if the top is gently pushed straight forward, it will eventually tend to curve either to the right or left, depending on which way it is spinning. Similarly, subject to the spin Hall effect, a quantum object spinning one way will, when pushed, curve off to one side, while if it spins the other way, it will curve to the other. The BEC followed this sort of curved path after the laser pushed it.

"This effect has been observed in solids before, but in solids there are other things happening that make it difficult to distinguish what the spin Hall effect is doing," says the research team's Matthew Beeler, who just completed a postdoctoral fellowship at NIST. "The good thing about seeing it in the BEC is that we've got a simple system whose properties we can explain in just two lines of equations. It means we can disentangle the spin Hall effect from the background and explore it more easily."

Conceptually, the laser setup can be thought of as an atom spin transistor—an atomtronic device—that can manipulate spin "currents" just as a conventional electronic transistor manipulates electrical current.

Beeler says that it is unlikely to be a practical way to build a logic gate for a working quantum computer, though. For now, he says, their new window into the spin Hall effect is good for researchers, who have wanted an easier way to understand complex systems where the effect appears. It also might provide insight into how data can be represented and moved from place to place in atomtronic circuits.

### *M.C. Beeler, R.A. Williams, K. Jiménez-García, L.J. LeBlanc, A.R. Perry and I.B. Spielman. The spin Hall effect in a quantum gas. Nature, published online June 5, 2013. DOI: 10.1038/nature12185.


ELSE PRESS RELEASES FROM THIS DATE:

Genetic mutation inherited from father's side linked to early puberty

2013-06-06
Boston, MA – Reaching puberty at an unusually early age can have adverse effects on social behavior and psychological development, as well as physical effects, including short stature, and lifelong health risks, such as diabetes, breast cancer and heart disease. Researchers at Brigham and Women's Hospital (BWH), in a multi-institutional collaboration with Boston Children's Hospital, the Broad Institute, and the University of Sao Paulo, Brazil, have identified that a genetic mutation leads to a type of premature puberty, known as central precocious puberty. Central precocious ...

Drug prevents post-traumatic stress-like symptoms in mice

2013-06-06
When injected into mice immediately following a traumatic event, a new drug prevents the animals from developing memory problems and increased anxiety that are indicative of post-traumatic stress disorder (PTSD). Howard Hughes Medical Institute scientists utilized mouse studies to suggest that a receptor called Oprl1 is altered in mice with PTSD-like symptoms. They then worked with a group at the Scripps Research Institute who had previously developed the Oprl1-targeted drug to examine its effects on fear memory modulation. The group has also shown that in humans, ...

University of Maryland School of Medicine finds gut bacteria play key role in vaccination

2013-06-06
Baltimore, Md. — June 5, 2013. The bacteria that live in the human gut may play an important role in immune response to vaccines and infection by wild-type enteric organisms, according to two recent studies resulting from a collaborative effort between the University of Maryland School of Medicine Institute for Genome Sciences and the Center for Vaccine Development. The first study, published online in PLOS ONE, http://umm.gd/13E3OHl, examines the impact of an oral typhoid vaccination on the microbiota, or populations of bacteria, in the human gut. The second study, also ...

Noble way to low-cost fuel cells, halogenated graphene may replace expensive platinum

2013-06-06
Ulsan, South Korea– The research team of Ulsan National Institute of Science and Technology (UNIST), Case Western Reserve University and University of North Texas have paved a new way for affordable commercialization of fuel cells with efficient metal-free electrocatalysts using edge-halogenated graphene nanoplatelets. Fuel cell technology has come a long way since the early days in the Apollo space program. Certainly the idea of running a car on pure hydrogen is an exciting prospect as the only emissions will be pure water. But how much will you be willing to pay ...

Ancient trapped water explains Earth's first ice age

2013-06-06
Tiny bubbles of water found in quartz grains in Australia may hold the key to understanding what caused the Earth's first ice age, say scientists. The Anglo-French study, published in the journal Nature, analysed the amount of ancient atmospheric argon gas (Ar) isotopes dissolved in the bubbles and found levels were very different to those in the air we breathe today. The researchers say their findings help explain why Earth didn't suffer its first ice age until 2.5 billion years ago, despite the Sun's rays being weaker during the early years of our planet's formation. "The ...

New study rebuts increase in willingness to cooperate from intuitive thinking

2013-06-06
The first study drew the conclusion that people cooperate more if they are forced to make decisions when pressed for time. The research group (Rand et al.) let the test subjects make decisions under pressure on social dilemmas. They found that the decisions made at the time were more oriented towards cooperation. The conclusion was that decisions under pressure that build on intuition promote cooperation. It has gotten a lot of attention and aroused a great deal of discussion. But it is not true, argues a group of researchers at several universities, including Linköping ...

Firefighting robot paints 3-D thermal imaging picture for rescuers

2013-06-06
Engineers in the Coordinated Robotics Lab at the University of California, San Diego, have developed new image processing techniques for rapid exploration and characterization of structural fires by small Segway-like robotic vehicles. A sophisticated on-board software system takes the thermal data recorded by the robot's small infrared camera and maps it onto a 3D scene constructed from the images taken by a pair of stereo RGB cameras. This allows small mobile robotic vehicles to create a virtual reality picture that includes a 3D map and temperature data that can ...

Bacillus thuringiensis Cry4B toxin kills Anopheles gambiae, a principal vector of malaria

2013-06-06
Researchers at The University of Texas at Dallas (UTD), led by Dr. Lee Bulla, have characterized a protein produced by the soil bacterium Bacillus thuringiensis subsp. israelensis (Bti), which is highly toxic against Anopheles gambiae, the principal mosquito vector of malaria. The protein toxin, which has been known for a number of years, is produced in a complex of other protein toxins, called Cry toxins, which also have mosquitocidal activity against other species of mosquito. The novelty of the research done by the UTD scientists is that they differentially fractionated ...

Detecting lead hotspots in urban gardens requires different sampling strategies

2013-06-06
DETROIT — The local food movement is gaining traction in cities across America, with urban gardens contributing a healthy source of fresh produce for local citizens as well as providing a social outlet for gardeners and creating open spaces for residents to enjoy. Urban gardening is not without risks, however. Many garden plots within cities were previously inhabited by residences or industrial buildings that disposed of toxic chemicals on site, creating potential health hazards from the use of lead in paint, gasoline and industrial activities. To properly assess the ...

NJIT researcher shows data mining EMRs can detect bad drug reactions

2013-06-06
NJIT Assistant Professor Mei Liu, PhD, a computer scientist, has recently shown in a new study that electronic medical records can validate previously reported adverse drug reactions and report new ones. "Comparative Analysis of Pharmacovigilance Methods in Detection of Adverse Drug Reactions from Electronic Medical Records" (Journal of American Medical Informatics Association, May 2013) examined the use of retrospective medication orders and inpatient laboratory results documented in the medical records to identify adverse reactions. Twelve years of data from Vanderbilt ...

LAST 30 PRESS RELEASES:

Fat may play an important role in brain metabolism

New study finds no lasting impact of pandemic pet ownership on human well-being

New insights on genetic damage of some chemotherapies could guide future treatments with less harmful side effects

Gut microbes could protect us from toxic ‘forever chemicals’

Novel modelling links sea ice loss to Antarctic ice shelf calving events

Scientists can tell how fast you're aging from a single brain scan

U.S. uterine cancer incidence and mortality rates expected to significantly increase by 2050

Public take the lead in discovery of new exploding star

What are they vaping? Study reveals alarming surge in adolescent vaping of THC, CBD, and synthetic cannabinoids

ECMWF - delivering forecasts over 10 times faster and cutting energy usage by 1000

Brazilian neuroscientist reveals how viral infections transform the brain through microscopic detective work

Turning social fragmentation into action through discovering relatedness

Cheese may really be giving you nightmares, scientists find

Study reveals most common medical emergencies in schools

Breathable yet protective: Next-gen medical textiles with micro/nano networks

Frequency-engineered MXene supercapacitors enable efficient pulse charging in TENG–SC hybrid systems

Developed an AI-based classification system for facial pigmented lesions

Achieving 20% efficiency in halogen-free organic solar cells via isomeric additive-mediated sequential processing

New book Terraglossia reclaims language, Country and culture

The most effective diabetes drugs don't reach enough patients yet

Breast cancer risk in younger women may be influenced by hormone therapy

Strategies for staying smoke-free after rehab

Commentary questions the potential benefit of levothyroxine treatment of mild hypothyroidism during pregnancy

Study projects over 14 million preventable deaths by 2030 if USAID defunding continues

New study reveals 33% gap in transplant access for UK’s poorest children

Dysregulated epigenetic memory in early embryos offers new clues to the inheritance of polycystic ovary syndrome (PCOS)

IVF and IUI pregnancy rates remain stable across Europe, despite an increasing uptake of single embryo transfer

It takes a village: Chimpanzee babies do better when their moms have social connections

From lab to market: how renewable polymers could transform medicine

Striking increase in obesity observed among youth between 2011 and 2023

[Press-News.org] First observation of spin Hall effect in a quantum gas is step toward 'atomtronics'