(Press-News.org) The electronics we use for our computers only knows two different states: zero or one. Quantum systems on the other hand can be in different states at once, they can store a superposition of "zero" and "one". This phenomenon could be used to build ultrafast quantum computers, but there are several technological obstacles that have to be overcome first. The biggest problem is that quantum states are quickly destroyed due to interactions with the environment. At TU Wien (Vienna), scientists have now succeeded in using a protection effect to enhance the stability of a particularly promising quantum system.
A Quantum Computer Made of Two Systems
There are various concepts for possible quantum computers. "What we use is a hybrid system of two completely different quantum technologies", says Johannes Majer. Together with his team, he couples microwaves and atoms, investigating and building a new type of quantum memory. The theorists Dmitry Krimer and Stefan Rotter developed a theoretical model describing the complex dynamics in such hybrid quantum systems.
In a microwave resonator, photons are created. They interact with the spin of nitrogen atoms, which are built into a diamond. The microwave resonator can be used to quickly transport quantum information. The atomic spins in the diamond can store it – at least for a period of several hundred nanoseconds, which is long compared to the time scale on which photons move in the microwave resonator.
"All nitrogen atoms are completely identical. But when they are placed in slightly different surroundings, they have slightly different transition frequencies", says Stefan Putz, PhD-student at Vienna University of Technology. The atomic spins behave like a room full of pendulum clocks. Initially they may oscillate in sync, but as they can never be precisely identical, they eventually lose their rhythm, creating random noise.
Coupling Causes Order
"By creating a strong coupling between the atomic spins and the resonator, it is possible to dramatically prolong the time during which the spins oscillate in strict time – if their energy levels obey the right distribution", says Dmitry Krimer. The atomic spins do not directly interact with each other, but the mere fact that they are collectively coupled to the microwave resonator prevents them from changing into a state in which they cannot be used for processing quantum information any longer. This protection effect considerably enhances the duration in which quantum information can be read out from the atomic spins.
"Improving the quantum coherence time with this cavity protection effect opens up many promising applications for our hybrid quantum system", says Johannes Majer.
The paper has now been published in Nature Physics.
INFORMATION:
Further information
Dr. Johannes Majer
Institute for Atomic and Subatomic Physics
TU Wien
Stadionallee 2, 1020 Wien
T: +43-1-58801-141838
johannes.majer@tuwien.ac.at
'Cavity protection effect' helps to conserve quantum information
Coupling atomic spins in diamonds to microwave resonators could lead to new quantum technologies. Researchers at the Vienna University of Technology (TU Wien) have now managed to dramatically prolong the time these systems can store information
2014-08-17
ELSE PRESS RELEASES FROM THIS DATE:
FDA-approved drug restores hair in patients with Alopecia Areata
2014-08-17
NEW YORK, NY (August 17, 2014) —Researchers at Columbia University Medical Center (CUMC) have identified the immune cells responsible for destroying hair follicles in people with alopecia areata, a common autoimmune disease that causes hair loss, and have tested an FDA-approved drug that eliminated these immune cells and restored hair growth in a small number of patients.
The results appear in today's online issue of Nature Medicine.
In the paper, the researchers report initial results from an ongoing clinical trial of the drug, which has produced complete hair regrowth ...
Fascinating rhythm: Light pulses illuminate a rare black hole
2014-08-17
The universe has so many black holes that it's impossible to count them all. There may be 100 million of these intriguing astral objects in our galaxy alone. Nearly all black holes fall into one of two classes: big, and colossal. Astronomers know that black holes ranging from about 10 times to 100 times the mass of our sun are the remnants of dying stars, and that supermassive black holes, more than a million times the mass of the sun, inhabit the centers of most galaxies.
But scattered across the universe like oases in a desert are a few apparent black holes of a more ...
A shift in the code: New method reveals hidden genetic landscape
2014-08-17
Cold Spring Harbor, NY – With three billion letters in the human genome, it seems hard to believe that adding a DNA base here or removing a DNA base there could have much of an effect on our health. In fact, such insertions and deletions can dramatically alter biological function, leading to diseases from autism to cancer. Still, it is has been difficult to detect these mutations. Now, a team of scientists at Cold Spring Harbor Laboratory (CSHL) has devised a new way to analyze genome sequences that pinpoints so-called insertion and deletion mutations (known as "indels") ...
New home for an 'evolutionary misfit'
2014-08-17
One of the most bizarre-looking fossils ever found - a worm-like creature with legs, spikes and a head difficult to distinguish from its tail – has found its place in the evolutionary Tree of Life, definitively linking it with a group of modern animals for the first time.
The animal, known as Hallucigenia due to its otherworldly appearance, had been considered an 'evolutionary misfit' as it was not clear how it related to modern animal groups. Researchers from the University of Cambridge have discovered an important link with modern velvet worms, also known as onychophorans, ...
Stem cells reveal how illness-linked genetic variation affects neurons
2014-08-17
VIDEO:
Human neurons firing
Click here for more information.
A genetic variation linked to schizophrenia, bipolar disorder and severe depression wreaks havoc on connections among neurons in the developing brain, a team of researchers reports. The study, led by Guo-li Ming, M.D., Ph.D., and Hongjun Song, Ph.D., of the Johns Hopkins University School of Medicine and described online Aug. 17 in the journal Nature, used stem cells generated from people with and without mental illness ...
New Stanford research sheds light on how children's brains memorize facts
2014-08-17
As children learn basic arithmetic, they gradually switch from solving problems by counting on their fingers to pulling facts from memory. The shift comes more easily for some kids than for others, but no one knows why.
Now, new brain-imaging research gives the first evidence drawn from a longitudinal study to explain how the brain reorganizes itself as children learn math facts. A precisely orchestrated group of brain changes, many involving the memory center known as the hippocampus, are essential to the transformation, according to a study from the Stanford University ...
Suspect gene corrupts neural connections
2014-08-17
Researchers have long suspected that major mental disorders are genetically-rooted diseases of synapses – the connections between neurons. Now, investigators supported in part by the National Institutes of Health have demonstrated in patients' cells how a rare mutation in a suspect gene disrupts the turning on and off of dozens of other genes underlying these connections.
"Our results illustrate how genetic risk, abnormal brain development and synapse dysfunction can corrupt brain circuitry at the cellular level in complex psychiatric disorders," explained Hongjun Song, ...
Stuck in neutral: Brain defect traps schizophrenics in twilight zone
2014-08-17
People with schizophrenia struggle to turn goals into actions because brain structures governing desire and emotion are less active and fail to pass goal-directed messages to cortical regions affecting human decision-making, new research reveals.
Published in Biological Psychiatry, the finding by a University of Sydney research team is the first to illustrate the inability to initiate goal-directed behaviour common in people with schizophrenia.
The finding may explain why people with schizophrenia have difficulty achieving real-world goals such as making friends, completing ...
Virginity pledges for men can lead to sexual confusion -- even after the wedding day
2014-08-17
Bragging of sexual conquests, suggestive jokes and innuendo, and sexual one-upmanship can all be a part of demonstrating one's manhood, especially for young men eager to exert their masculinity.
But how does masculinity manifest itself among young men who have pledged sexual abstinence before marriage? How do they handle sexual temptation, and what sorts of challenges crop up once they're married?
"Sexual purity and pledging abstinence are most commonly thought of as feminine, something girls and young women promise before marriage," said Sarah Diefendorf, a sociology ...
Study finds range of skills students taught in school linked to race and class size
2014-08-17
SAN FRANCISCO -- Pressure to meet national education standards may be the reason states with significant populations of African-American students and those with larger class sizes often require children to learn fewer skills, finds a University of Kansas researcher.
"The skills students are expected to learn in schools are not necessarily universal," said Argun Saatcioglu, a KU associate professor of education and courtesy professor of sociology.
In effort to increase their test scores and, therefore, avoid the negative consequences of failing to meet the federal standards ...
LAST 30 PRESS RELEASES:
Heart rhythm disorder traced to bacterium lurking in our gums
American Society of Plant Biologists names 2025 award recipients
Protecting Iceland’s towns from lava flows – with dirt
Noninvasive intracranial source signal localization and decoding with high spatiotemporal resolution
A smarter way to make sulfones: Using molecular oxygen and a functional catalyst
Self-assembly of a large metal-peptide capsid nanostructure through geometric control
Fatty liver in pregnancy may increase risk of preterm birth
World record for lithium-ion conductors
Researchers map 7,000-year-old genetic mutation that protects against HIV
KIST leads next-generation energy storage technology with development of supercapacitor that overcomes limitations
Urine, not water for efficient production of green hydrogen
Chip-scale polydimethylsiloxane acousto-optic phase modulator boosts higher-resolution plasmonic comb spectroscopy
Blood test for many cancers could potentially thwart progression to late stage in up to half of cases
Women non-smokers still around 50% more likely than men to develop COPD
AI tool uses face photos to estimate biological age and predict cancer outcomes
North Korea’s illegal wildlife trade threatens endangered species
Health care workers, firefighters have increased PFAS levels, study finds
Turning light into usable energy
Important step towards improving diagnosis and treatment of brain metastases
Maternal cardiometabolic health during pregnancy associated with higher blood pressure in children, NIH study finds
Mercury levels in the atmosphere have decreased throughout the 21st century
This soft robot “thinks” with its legs
Biologists identify targets for new pancreatic cancer treatments
Simple tweaks to a gene underlie the stench of rotten-smelling flowers
Simple, effective interventions reduce emissions from Bangladesh’s informal brick kilns
Ultrasound-guided 3D bioprinting enables deep-tissue implant fabrication in vivo
Soft limbs of flexible tubes and air enable dynamic, autonomous robotic locomotion
Researchers develop practical solution to reduce emissions and improve air quality from brick manufacturing in Bangladesh
Durham University scientists solve 500-million-year fossil mystery
Red alert for our closest relatives
[Press-News.org] 'Cavity protection effect' helps to conserve quantum informationCoupling atomic spins in diamonds to microwave resonators could lead to new quantum technologies. Researchers at the Vienna University of Technology (TU Wien) have now managed to dramatically prolong the time these systems can store information