Featured Research

from universities, journals, and other organizations

Diamond defect interior design: Planting imperfections at specific spots within a diamond lattice could advance quantum computing

Date:
August 5, 2014
Source:
American Institute of Physics (AIP)
Summary:
By carefully controlling the position of an atomic-scale diamond defect within a volume smaller than what some viruses would fill, researchers have cleared a path toward better quantum computers and nanoscale sensors.

A surface confocal scan of a diamond sample shows the NV centers in yellow. A single NV center is circled in red. The inset scanning electron microscope image shows holes in a separate sample as tiny dimples.
Credit: F.J. Heremans and D. Awschalom/U. Chicago and K. Ohno/UCSB

By carefully controlling the position of an atomic-scale diamond defect within a volume smaller than what some viruses would fill, researchers have cleared a path toward better quantum computers and nanoscale sensors. They describe their technique in a paper published in the journal Applied Physics Letters, from AIP Publishing.

Related Articles


David Awschalom, a physicist at the Institute for Molecular Engineering at the University of Chicago, and his colleagues study a technologically useful diamond defect called a nitrogen vacancy (NV) center. NV centers consist of a nitrogen atom adjacent to a vacant spot that replaces two carbon atoms in the diamond crystal, leaving an unpaired electron. Researchers can use a property of the unpaired electron known as its spin to store and transmit quantum information at room temperature.

Qubits and Quantum Sensors

NV centers are attractive candidates for qubits, the quantum equivalent of a classical computing bit. A single NV center can also be used for completely different applications, such as measuring temperature, as well as to image electric and magnetic fields on the nanometer-scale by placing it at the tip of a diamond-based scanning probe.

A primary obstacle to further exploiting NV centers for practical quantum computing and nanoscale sensing devices lies in the difficulty of placing the centers within what Awschalom calls the functional "sweet spots" of the devices. Another challenge is increasing the NV center density without sacrificing their spin lifetimes, which must remain long in order to extract the most useful information from the system.

Awschalom and his colleagues have developed a new way to create NV centers that could help overcome both these challenges.

That's the Spot

The key to the team's new approach is to create the nitrogen and vacancy defects separately, Awschalom said. First, the team grew a layer of nitrogen-doped crystal within a diamond film. The researchers kept the nitrogen layer extremely thin by reducing the growth rate of the film to approximately 8 nanometers/hour. The nanometer-scale nitrogen-doped layer constrains the possible location of the NV centers in the depth direction.

Secondly, the researchers created a mask to cover the film, leaving only pinprick holes. They blasted carbon ions through the holes to create vacancies and heated the diamond to make the vacancies mobile within the crystal. NV centers could form in the nitrogen-doped layer below where the holes were placed.

Using this approach the team successfully localized NV centers within a cavity approximately 180 nanometers across -- a volume small enough to be compatible with many diamond-based nanostructures used in sensing devices and experimental quantum information systems.

The localized NV centers could also hold a specific spin for longer than 300 microseconds. This so-called spin coherence time was an order of magnitude better than that achieved by other 3-D localization methods. The longer spin lifetime means the NV centers can detect smaller magnetic signals and hold quantum information for longer.

One of the team's goals for using their new technique is to measure the nuclear spins of hydrogen atoms -- one of the tiniest magnetic signals -- within a biological molecule. The research could reveal new insights into how important biological functions like photosynthesis work. "Our research impacts diverse fields of science and technology," Awschalom said. "Technological advancements always open new avenues of scientific research."


Story Source:

The above story is based on materials provided by American Institute of Physics (AIP). Note: Materials may be edited for content and length.


Journal Reference:

  1. Kenichi Ohno, F. Joseph Heremans, Charles F. de las Casas, Bryan A. Myers, Benjamνn J. Alemαn, Ania C. Bleszynski Jayich, and David D. Awschalom. Three-dimensional localization of spins in diamond using 12C implantation. Applied Physics Letters, August 5, 2014 DOI: 10.1063/1.4890613

Cite This Page:

American Institute of Physics (AIP). "Diamond defect interior design: Planting imperfections at specific spots within a diamond lattice could advance quantum computing." ScienceDaily. ScienceDaily, 5 August 2014. <www.sciencedaily.com/releases/2014/08/140805131716.htm>.
American Institute of Physics (AIP). (2014, August 5). Diamond defect interior design: Planting imperfections at specific spots within a diamond lattice could advance quantum computing. ScienceDaily. Retrieved April 18, 2015 from www.sciencedaily.com/releases/2014/08/140805131716.htm
American Institute of Physics (AIP). "Diamond defect interior design: Planting imperfections at specific spots within a diamond lattice could advance quantum computing." ScienceDaily. www.sciencedaily.com/releases/2014/08/140805131716.htm (accessed April 18, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Saturday, April 18, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

NASA Electric Rover Goes for a Spin

NASA Electric Rover Goes for a Spin

Reuters - Innovations Video Online (Apr. 17, 2015) — NASA&apos;s prototype electric buggy could influence future space rovers and conventional cars. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Scientists Create Self-Powering Camera

Scientists Create Self-Powering Camera

Reuters - Innovations Video Online (Apr. 17, 2015) — American scientists build a self-powering camera that captures images without using an external power source, allowing it to operate indefinitely in a well-lit environment. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
The State Of Virtual Reality

The State Of Virtual Reality

Newsy (Apr. 17, 2015) — Virtual Reality is still a young industry. What’s on offer and what should we expect from our immersive new future? Video provided by Newsy
Powered by NewsLook.com
Tackling Congestion in the World's Worst Traffic City

Tackling Congestion in the World's Worst Traffic City

Reuters - News Video Online (Apr. 16, 2015) — New transportation system and regulations aim to resolve gridlock in Jakarta, which has been named the city with the world&apos;s worst traffic. Angie Teo reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins