Matter News
Recent News |  Archives |  Tags |  About |  Newsletter |  Submit News |  Links |  Subscribe to MatterNews.com RSS Feed Subscribe


More Articles
Batteries included: A solar cell that stores its own powerBatteries included: A solar cell that stores its own power

Lift weights, improve your memoryLift weights, improve your memory

Beyond LEDs: Brighter, new energy-saving flat panel lights based on carbon nanotubesBeyond LEDs: Brighter, new energy-saving flat panel lights based on carbon nanotubes

Hubble project maps temperature, water vapor on wild exoplanetHubble project maps temperature, water vapor on wild exoplanet

Structure of an iron-transport protein revealedStructure of an iron-transport protein revealed

First step: From human cells to tissue-engineered esophagusFirst step: From human cells to tissue-engineered esophagus

Autophagy helps fast track stem cell activationAutophagy helps fast track stem cell activation

Charged graphene gives DNA a stage to perform molecular gymnasticsCharged graphene gives DNA a stage to perform molecular gymnastics

A unique approach to monitoring groundwater supplies near Ohio fracking sitesA unique approach to monitoring groundwater supplies near Ohio fracking sites

Myelin vital for learning new practical skillsMyelin vital for learning new practical skills

Spiders: Survival of the fittest groupSpiders: Survival of the fittest group

More physical activity improved school performanceMore physical activity improved school performance

Building a bridge from basic botany to applied agricultureBuilding a bridge from basic botany to applied agriculture

Engineering new vehicle powertrainsEngineering new vehicle powertrains

Stunning finds from ancient Greek shipwreckStunning finds from ancient Greek shipwreck

Around the world in 400,000 years: The journey of the red foxAround the world in 400,000 years: The journey of the red fox

Active aging is much more than exerciseActive aging is much more than exercise

Study: New device can slow, reverse heart failureStudy: New device can slow, reverse heart failure

Are the world's religions ready for ET?Are the world's religions ready for ET?

Gut bacteria, artificial sweeteners and glucose intoleranceGut bacteria, artificial sweeteners and glucose intolerance

Recreating the stripe patterns found in animals by engineering synthetic gene networksRecreating the stripe patterns found in animals by engineering synthetic gene networks

Laying the groundwork for data-driven scienceLaying the groundwork for data-driven science

Hold on, tiger momHold on, tiger mom

Nature's designs inspire research into new light-based technologiesNature's designs inspire research into new light-based technologies

Missing piece found to help solve concussion puzzleMissing piece found to help solve concussion puzzle

Biologists delay the aging process by 'remote control'Biologists delay the aging process by 'remote control'

Geography matters: Model predicts how local 'shocks' influence U.S. economyGeography matters: Model predicts how local 'shocks' influence U.S. economy

Identified for the first time what kind of explosive has been used after the detonationIdentified for the first time what kind of explosive has been used after the detonation

Copied from nature: Detecting software errors via genetic algorithmsCopied from nature: Detecting software errors via genetic algorithms

On the road to fault-tolerant quantum computing (9/18/2013)

Tags:
computing, electrons, elements, energy, films, insulators, light, magnetic vortices, material, materials, photoemission, photons, quantum computing, qubits, strontium, superconductivity, surfaces, temperature, ultraviolet, ultraviolet light
This schematic of a bismuth selenide/BSCCO cuprate (Bi2212) heterostructure shows a proximity-induced high-temperature superconducting gap on the surface states of the bismuth selenide topological insulator. -  Image courtesy of Berkeley Lab
This schematic of a bismuth selenide/BSCCO cuprate (Bi2212) heterostructure shows a proximity-induced high-temperature superconducting gap on the surface states of the bismuth selenide topological insulator. - Image courtesy of Berkeley Lab

Reliable quantum computing would make it possible to solve certain types of extremely complex technological problems millions of times faster than today's most powerful supercomputers. Other types of problems that quantum computing could tackle would not even be feasible with today's fastest machines. The key word is "reliable." If the enormous potential of quantum computing is to be fully realized, scientists must learn to create "fault-tolerant" quantum computers. A small but important step toward this goal has been achieved by an international collaboration of researchers from China's Tsinghua University and the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) working at the Advanced Light Source (ALS).

Using premier beams of ultraviolet light at the ALS, a DOE national user facility for synchrotron radiation, the collaboration has reported the first demonstration of high-temperature superconductivity in the surface of a topological insulator - a unique class of advanced materials that are electrically insulating on the inside but conducting on the surface. Inducing high-temperature superconductivity on the surface of a topological insulator opens the door to the creation of a pre-requisite for fault-tolerant quantum computing, a mysterious quasiparticle known as the "Majorana zero mode."

"We have shown that by interfacing a topological insulator, bismuth selenide, with a high temperature superconductor, BSCCO (bismuth strontium calcium copper oxide), it is possible to induce superconductivity in the topological surface state," says Alexei Fedorov, a staff scientist for ALS beamline 12.0.1, where the induced high temperature superconductivity of the topological insulator heterostructure was confirmed. "This is the first reported demonstration of induced high temperature superconductivity in a topological surface state."

The results of this research are presented in the journal Nature Physics in a paper titled "Fully gapped topological surface states in Bi2Se3 induced by a d-wave high temperature superconductor." The corresponding authors are Shuyun Zhou and Xi Chen of Tsinghua University in Beijing, China. The lead authors are Eryin Wang and Hao Ding, also with Tsinghua University. Wang is currently an ALS Doctoral fellow in residence.

For all of its boundless potential, quantum computing faces a serious flaw. The quantum data bit or "qubit" used to process and store information is fragile and easily perturbed by electrons and other elements in its surrounding environment. Utilizing topological insulators is considered one promising approach for solving this "decoherence" problem because qubits in a topological quantum computer would be made from Majorana zero modes, which are naturally immune from decoherence. Information processed and stored in such topological qubits would always be preserved. While the ALS collaboration has not yet identified a Majorana zero mode in their bismuth selenide/BSCCO heterostructures, they believe their material is fertile ground for doing so.

"Our studies reveal a large superconducting pairing gap on the topological surface states of thin films of the bismuth selenide topological insulator when grown on BSCCO," Fedorov says. "This suggests that Majorana zero modes are likely to exist, bound to magnetic vortices in this material, but we will have to do other types of measurements to find it."

The high quality bismuth selenide/BSCCO topological thin film heterostructure was made at Tsinghua University in the laboratory of Xi Chen and Qi-Kun Xue using molecular beam epitaxy.

"Our study was made possible by the high quality topological insulator film heterostructure that the Chen and Xue groups managed to grow," says Zhou, who did much of her research at the ALS before returning to China. "Bismuth selenide and the BSSCO ceramic have very different crystal structures and symmetries, which made the growth of such a heterostructure particularly challenging."

Says Chen, "By controlling the growth kinetics carefully using molecular beam epitaxy, we managed to grow a topological insulator film with controlled thickness on a freshly cleaved BSCCO surface. This provided a cleaner and better-controlled interface, and also opened up opportunities for surface sensitive measurements."

The bismuth selenide/BSCCO material was brought to the ALS to study the electronic states on its surface using a technique known as ARPES, for angle-resolved photoemission spectroscopy. In ARPES, a beam of X-ray photons striking the material's surface causes the photoemission of electrons. The kinetic energy of these photoelectrons and the angles at which they are ejected are then measured to obtain an electronic spectrum.

"Previous work on topological insulators revealed superconductivity at only a few Kelvin with a gap of about one milli-electron volt," Fedorov says. "Such a small energy scale and ultra-low temperature makes it particularly challenging to realize Majorana zero modes experimentally, and to distinguish these modes from other states. Using ARPES, we show evidence of a superconducting gap persisting in the surfaces of our material up to the transition temperature of BSCCO. As the gap and transition temperature in our heterostructure reflect almost an order of magnitude increase over previous work, we believe ours is a better system to search for Majorana zero modes."

Note: This story has been adapted from a news release issued by the DOE/Lawrence Berkeley National Laboratory

Post Comments:

Search
New Articles
A 'Star Wars' laser bullet -- this is what it really looks likeA 'Star Wars' laser bullet -- this is what it really looks like

Curious signal hints at dark matterCurious signal hints at dark matter

Magnetic mirrors enable new technologies by reflecting light in uncanny waysMagnetic mirrors enable new technologies by reflecting light in uncanny ways

Protons hog the momentum in neutron-rich nucleiProtons hog the momentum in neutron-rich nuclei

New book about life as seen from physicsNew book about life as seen from physics

'Dressing' in superconductors'Dressing' in superconductors

Team explore power of thorium for improved nuclear design

Leads research on new materials that could make it safer to store nuclear waste

Tailored flexible illusion coatings hide objects from detection

Rare 'baby rattle' molecules reveal new quantum properties of H2O and H2

Old textbook knowledge reconfirmed: Decay rates of radioactive substances are constantOld textbook knowledge reconfirmed: Decay rates of radioactive substances are constant

Dark matter half what we thought, say scientistsDark matter half what we thought, say scientists

Fusion reactor concept could be cheaper than coalFusion reactor concept could be cheaper than coal

A quick look at electron-boson couplingA quick look at electron-boson coupling

Fundamentals of physics confirmed



Archives
October 2014
September 2014
August 2014
July 2014
June 2014
May 2014
April 2014
March 2014
February 2014
January 2014
December 2013
November 2013
October 2013
September 2013
August 2013
July 2013
June 2013
May 2013
April 2013
March 2013
February 2013
January 2013
December 2012
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
December 2011
November 2011
October 2011
September 2011
August 2011
July 2011
June 2011
May 2011
April 2011
March 2011
February 2011
January 2011
December 2010
November 2010
October 2010
September 2010
August 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
November 2009
October 2009
September 2009
August 2009
July 2009
June 2009
May 2009
April 2009
March 2009
February 2009
January 2009
December 2008
November 2008
October 2008
September 2008
August 2008
July 2008
June 2008
May 2008
April 2008
March 2008
February 2008
January 2008
December 2007
November 2007
October 2007
September 2007
August 2007


Science Friends
Agricultural Science
Astronomy News
Biology News
Biomimicry Science
Cognitive Research
Chemistry News
Tissue Engineering
Cancer Research
Cybernetics Research
Electonics Research
Forensics Report
Fossil News
Genetic Archaeology
Genetics News
Geology News
Nanotech News
Parenting News


  Archives |  Submit News |  Advertise With Us |  Contact Us |  Links
Use of this site constitutes acceptance of our Terms of Service and Privacy Policy. All contents © 2000 - 2015 Web Doodle, LLC. All rights reserved.