Quantum computers counting on carbon nanotubes

Physicists develop a new approach to quantum computing

2013-03-21

(Press-News.org) Using quantum mechanical phenomena, computers could be much more powerful than their classical digital predecessors. Scientists all over the world are working to explore the basis for quantum computing. To date most systems are based on electrically charged particles that are held in an "electromagnetic trap." A disadvantage of these systems is that they are very sensitive to electromagnetic interference and therefore need extensive shielding. Physicists at the Technische Universitaet Muenchen have now found a way for information to be stored and quantum mechanically processed in mechanical vibrations.

Playing a nano-guitar

A carbon nanotube that is clamped at both ends can be excited to oscillate. Like a guitar string, it vibrates for an amazingly long time. "One would expect that such a system would be strongly damped, and that the vibration would subside quickly," says Simon Rips, first author of the publication. "In fact, the string vibrates more than a million times. The information is thus retained up to one second. That is long enough to work with."

Since such a string oscillates among many physically equivalent states, the physicists resorted to a trick: an electric field in the vicinity of the nanotube ensures that two of these states can be selectively addressed. The information can then be written and read optoelectronically. "Our concept is based on available technology," says Michael Hartmann, head of the Emmy Noether research group Quantum Optics and Quantum Dynamics at the TU Muenchen. "It could take us a step closer to the realization of a quantum computer."

INFORMATION:

Publication:

Quantum Information Processing with Nanomechanical Qubits
Simon Rips and Michael J. Hartmann,
Physical Review Letters, 110, 120503 (2013) DOI: 10.1103/PhysRevLett.110.120503
Link: http://prl.aps.org/abstract/PRL/v110/i12/e120503

[Attachments] See images for this press release:

ELSE PRESS RELEASES FROM THIS DATE:

Discovery could increase efficacy of promising cystic fibrosis drug

2013-03-21

A little more than a year after the FDA approved Kalydeco (Vx-770), the first drug of its kind to treat the underlying cause of cystic fibrosis, University of Missouri researchers believe they have found exactly how this drug works and how to improve its effectiveness in the future. Described in the current issue of the Proceedings of the National Academy of Sciences, MU researchers have redefined a key regulatory process in the defective protein responsible for cystic fibrosis that could change the way scientists approach the lethal genetic disease. "They know the drug ...

The Seven Star Global Luxury Awards has Confirmed their Final Travel, Tourism and Hospitality Nominees; With Voting Now Open to the Public and Trade...

2013-03-21

The Seven Star Global Luxury Awards continues to gain momentum with online voting already exceeding expectations after only a few weeks. With the most sought-after brands in the travel, tourism and hospitality industries vying to be honored with the Signum Virtutis - the seal of excellence, being bestowed upon them for 2013; competition is becoming fierce on a global scale. The results will be revealed at the Awards Ceremony; honoring this elite collection of nominees with this highest and most exclusive award for being the pinnacle of luxury and lifestyle in these ...

Warm springs may be best winter refuge for Florida manatees

2013-03-21

During the winter, manatees in Florida rely on warm-water refuges in the southern peninsula, and consistently return to one more specific areas. This new study assessed the proportion of manatees that use natural springs, power plant discharge areas, and passive 'thermal basins' that trap warm water for a week or more. They found that nearly half of all animals they counted sought out power plant outfalls for warmth, while approximately 17% chose warm springs. In the coldest periods the proportion at power plants can increase to two-thirds. Despite this relatively small ...

3-year olds know rules of sharing but don't follow them until older

2013-03-21

The authors note, "People who spend time with young children will know that they often favor themselves when sharing, but surprisingly they endorse equal sharing not just by other people but also in their own case. In our research, we were able to rule out a number of explanations for this early gap between word and deed." When the researchers gave 3-8-year-olds stickers they valued and asked them about sharing, children of all ages readily asserted that they themselves should share equally, and others should as well. However, when given the chance to actually share, ...

Fear factor increases, emotions decrease in books written in last 50 years

2013-03-21

The authors analyzed trends in the use of 'mood words' that convey joy, anger, fear and other emotions and found a general, overall decrease in the use of words that convey emotions. They found distinct historical periods of positive and negative moods in books that correlated with socio-political events like World War II, the Great Depression or the Baby Boom. In contrast to the five other moods studied, words that convey fear showed an opposite trend. Words conveying fear declined in use through the early 20th century but increased markedly since the 1970s, despite ...

Roman mausoleum tested for ancient earthquake damage

2013-03-21

Please cite the Bulletin of the Seismological Society of America (BSSA) as the source of this information. Built under a sheer cliff, with a commanding view of the forum and castle in the ancient city of Pinara in Turkey, a Roman mausoleum has been knocked off-kilter, its massive building blocks shifted and part of its pediment collapsed. The likely cause is an earthquake, according to a new detailed model by Klaus-G. Hinzen and colleagues at the University of Cologne. They conclude that a 6.3 magnitude earthquake could have caused the damage, and their new finding gives ...

Can intraplate earthquakes produce stronger shaking than at plate boundaries?

2013-03-21

Please cite the Bulletin of the Seismological Society of America (BSSA) as the source of this information. New information about the extent of the 1872 Owens Valley earthquake rupture, which occurs in an area with many small and discontinuous faults, may support a hypothesis proposed by other workers that these types of quakes could produce stronger ground shaking than plate boundary earthquakes underlain by oceanic crust, like many of those taking place along the San Andreas fault. Published estimates of the 1872 Owens Valley earthquake in southeastern California put ...

Maternal diabetes impairs methylation of imprinted gene in oocytes

2013-03-21

For the first time, researchers have shown that poorly controlled maternal diabetes has an adverse effect on methylation of the maternal imprinting gene Peg3, contributing to impaired development in offspring. Previous studies have revealed that offspring of diabetic mothers display a higher incidence of malformations and fetal death, even when a one-cell embryo is transplanted from a diabetic to a non-diabetic mother. Diabetic mothers' oocytes tend to exhibit reduced glucose metabolism, compromised communication between cumulus cells and oocytes, mitochondrial malfunction, ...

Researchers link Gulf War Illness to physical changes in brain fibers that process pain

2013-03-21

WASHINGTON — Researchers at Georgetown University Medical Center (GUMC) have found what they say is evidence that veterans who suffer from "Gulf War Illness" have physical changes in their brains not seen in unaffected individuals. Brain scans of 31 veterans with the illness, compared to 20 control subjects, revealed anomalies in the bundles of nerve fibers that connect brain areas involved in the processing and perception of pain and fatigue. The discovery, published online March 20 in PLOS ONE, could provide insight into the mysterious medical symptoms reported by more ...

Follow-up study describes declining efficacy of malaria vaccine candidate over 4 years

2013-03-21

Long-term follow-up of a phase II study from KEMRI-Wellcome Trust Research Programme and Oxford University researchers in Kenya shows that the efficacy of a malaria vaccine candidate, RTS,S, wanes over time and varies with exposure to the malaria parasite. The findings will help to inform which populations are likely to benefit most from the vaccine candidate. They also have important implications for the design of future clinical trials of this and other vaccine candidates and highlight the importance of long-term follow-up studies for assessing vaccine efficacy. The ...

LAST 30 PRESS RELEASES:

New platform could develop vaccines faster than ever before

TF-rs1049296 C>T variant modifies the association between hepatic iron stores and liver fibrosis in metabolic dysfunction-associated steatotic liver disease

ASH publishes clinical practice guidelines on diagnosis of light chain amyloidosis

SLAS receives grant from Alfred P. Sloan Foundation to develop lab automation educational guidelines

Serum interleukin-8 for differentiating invasive pulmonary aspergillosis from bacterial pneumonia in patients with HBV-associated acute-on-chronic liver failure