Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Building quantum states with individual silicon atoms

Scanning tunnelling microscopy (STM) images of the quantum states of an artificial atomic defect structure in silicon. This structure was fabricated by using the STM to individually remove five hydrogen atoms from a hydrogen-terminated silicon (001) surface. The absence of the hydrogen atoms creates "dangling bond" states that interact to form extended, artificial molecular orbitals. Only the imaging bias voltage has been changed in the three images shown (from left to right, -1.4, +1.4, and +1.8 Volts).
Scanning tunnelling microscopy (STM) images of the quantum states of an artificial atomic defect structure in silicon. This structure was fabricated by using the STM to individually remove five hydrogen atoms from a hydrogen-terminated silicon (001) surface. The absence of the hydrogen atoms creates "dangling bond" states that interact to form extended, artificial molecular orbitals. Only the imaging bias voltage has been changed in the three images shown (from left to right, -1.4, +1.4, and +1.8 Volts).

Abstract:
By introducing individual silicon atom 'defects' using a scanning tunnelling microscope, scientists at the London Centre for Nanotechnology have coupled single atoms to form quantum states.

Building quantum states with individual silicon atoms

London, UK | Posted on April 3rd, 2013

Published today in Nature Communications, the study demonstrates the viability of engineering atomic-scale quantum states on the surface of silicon - an important step toward the fabrication of devices at the single-atom limit.

Advances in atomic physics now allow single ions to be brought together to form quantum coherent states. However, to build coupled atomic systems in large numbers, as required for applications such as quantum computing, it is highly desirable to develop the ability to construct coupled atomic systems in the solid state.

Semiconductors, such as silicon, routinely display atomic defects that have clear analogies with trapped ions. However, introducing such defects deterministically to observe the coupling between extended systems of individual defects has so far remained elusive.

Now, LCN scientists have shown that quantum states can be engineered on silicon by creating interacting single-atom defects. Each individual defect consisted of a silicon atom with a broken, or "dangling", bond. During this study, these single-atom defects were created in pairs and extended chains, with each defect separated by just under one nanometer.

Importantly, when coupled together, these individual atomic defects produce extended quantum states resembling artificial molecular orbitals. Just as for a molecule, each structure exhibited multiple quantum states with distinct energy levels.

The visibility of these states to the scanning tunneling microscope could be tuned through the variation of two independent parameters - the voltage applied to the imaging probe and its height above the surface.

The study was led by Dr Steven Schofield, who said: "We have created precise arrays of atomic defects on a silicon surface and demonstrated that they couple to form unique and interesting quantum states."

He added: "The next step is to replicate these results in other material systems, for example using substitutional phosphorus atoms in silicon, which holds particular interest for quantum computer fabrication."

Ongoing research at the LCN is exploring even more complex arrangements of these defects, including the incorporation of impurity atoms within the defect structures, which is expected to alter the symmetry of the defects (similar to the role of the nitrogen atom in the nitrogen-vacancy center defect in diamond).

####

About University College London - UCL
Founded in 1826, UCL was the first English university established after Oxford and Cambridge, the first to admit students regardless of race, class, religion or gender and the first to provide systematic teaching of law, architecture and medicine.

We are among the world's top universities, as reflected by our performance in a range of international rankings and tables. According to the Thomson Scientific Citation Index, UCL is the second most highly cited European university and the 15th most highly cited in the world.

UCL has nearly 25,000 students from 150 countries and more than 9,000 employees, of whom one third are from outside the UK. The university is based in Bloomsbury in the heart of London, but also has two international campuses Ė UCL Australia and UCL Qatar. Our annual income is more than £800 million.

For more information, please click here

Contacts:
Clare Ryan
UCL Media Relations Office
tel: +44 (0)20 3108 3846
mobile: +44 07747 556 056
out of hours +44 (0)7917 271 364

Copyright © University College London - UCL

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Leti and Oscaro Partner on Letiís New Low-Power, Low-Cost Transceiver to Track Parcels July 12th, 2018

Oxford Instrumentsí 22 Tesla superconducting magnet system commissioned at the UAM, making it the most intense magnetic field available outside a large international facility July 12th, 2018

Physics

A refined magnetic sense: Algorithms and hardware developed in the context of quantum computation are shown to be useful for quantum-enhanced sensing of magnetic fields July 2nd, 2018

Evidence for a new property of quantum matter revealed: Electrical dipole activity detected in a quantum material unlike any other tested June 11th, 2018

Theory gives free rein to superconductivity at room temperature May 28th, 2018

Scientists Pinpoint Energy Flowing Through Vibrations in Superconducting Crystals: Interactions between electrons and the atomic structure of high-temperature superconductors impacted by elusive and powerful vibrations May 4th, 2018

Chip Technology

Nanometrics to Announce Second Quarter Financial Results on July 31, 2018 July 12th, 2018

Leti and Soitec Launch a New Substrate Innovation Center to Develop Engineered Substrate Solutions: Industry-inclusive hub promotes early collaboration and learning from substrate to system level July 11th, 2018

GLOBALFOUNDRIES Surpasses $2 Billion in Design Win Revenue on 22FDXģ Technology : With 50 client designs and growing, 22FDX proves its value as a cost-effective solution for power-sensitive applications July 9th, 2018

High-power electronics keep their cool with new heat-conducting crystals July 6th, 2018

Quantum Computing

A refined magnetic sense: Algorithms and hardware developed in the context of quantum computation are shown to be useful for quantum-enhanced sensing of magnetic fields July 2nd, 2018

Carbon nanotube optics poised to provide pathway to optical-based quantum cryptography and quantum computing: Researchers are exploring enhanced potential of carbon nanotubes for unique applications June 18th, 2018

Evidence for a new property of quantum matter revealed: Electrical dipole activity detected in a quantum material unlike any other tested June 11th, 2018

Tunable diamond string may hold key to quantum memory: A process similar to guitar tuning improves storage time of quantum memory May 24th, 2018

Discoveries

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides July 13th, 2018

Researchers identify cost-cutting option in treating nail fungus with nanotechnology: GW researcher Adam Friedman, M.D., studied the potential use of nitric oxide-releasing nanoparticles to improve onychomycosis treatment July 11th, 2018

Announcements

Nano-kirigami: 'Paper-cut' provides model for 3D intelligent nanofabrication July 13th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Barium ruthenate: A high-yield, easy-to-handle perovskite catalyst for the oxidation of sulfides July 13th, 2018

Leti and Oscaro Partner on Letiís New Low-Power, Low-Cost Transceiver to Track Parcels July 12th, 2018

Quantum nanoscience

Carbon nanotube optics poised to provide pathway to optical-based quantum cryptography and quantum computing: Researchers are exploring enhanced potential of carbon nanotubes for unique applications June 18th, 2018

Making quantum puddles: Physicists discover how to create the thinnest liquid films ever June 13th, 2018

Detecting the birth and death of a phonon June 7th, 2018

Quantum Interference May Be Key to Smaller Insulators: Breakthrough could jumpstart further miniaturization of transistors June 6th, 2018

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project