Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Flawed Diamonds Promise Sensory Perfection: Berkeley Lab researchers and their colleagues extend electron spin in diamond for incredibly tiny magnetic detectors

Nitrogen-vacancy centers are defects in which a nitrogen atom substitutes for a carbon atom in the lattice and a vacancy left by a missing carbon atom is immediately adjacent, leaving unbonded electrons whose states can be precisely controlled. NV centers occur naturally in diamond or can be created artificially.
Nitrogen-vacancy centers are defects in which a nitrogen atom substitutes for a carbon atom in the lattice and a vacancy left by a missing carbon atom is immediately adjacent, leaving unbonded electrons whose states can be precisely controlled. NV centers occur naturally in diamond or can be created artificially.

Abstract:
From brain to heart to stomach, the bodies of humans and animals generate weak magnetic fields that a supersensitive detector could use to pinpoint illnesses, trace drugs - and maybe even read minds. Sensors no bigger than a thumbnail could map gas deposits underground, analyze chemicals, and pinpoint explosives that hide from other probes.

Flawed Diamonds Promise Sensory Perfection: Berkeley Lab researchers and their colleagues extend electron spin in diamond for incredibly tiny magnetic detectors

Berkeley, CA | Posted on May 10th, 2013

Now scientists at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley, working with colleagues from Harvard University, have improved the performance of one of the most potent possible sensors of magnetic fields on the nanoscale - a diamond defect no bigger than a pair of atoms, called a nitrogen vacancy (NV) center.

The research team's discoveries may eventually enable clocks smaller than computer chips yet accurate to within a few quadrillionths of a second, or rotational sensors quicker and more tolerant of extreme temperatures than the gyroscopes in smart phones. Before long, an inexpensive chip of diamond may be able to house a quantum computer. The team reports their results in Nature Communications.

A sensor made of diamond

Nitrogen vacancy centers are some of the most common defects in diamonds. When a nitrogen atom substitutes for a carbon atom in the diamond crystal and pairs with an adjacent vacancy (where a carbon atom is missing altogether), a number of electrons not bonded to the missing carbon atoms are left in the center.

The electron spin states are well defined and very sensitive to magnetic fields, electric fields, and light, so they can easily be set, adjusted, and read out by lasers.

"The spin states of NV centers are stable across a wide range of temperatures from very hot to very cold," says Dmitry Budker of Berkeley Lab's Nuclear Science Division, who is also a physics professor at UC Berkeley. Even tiny flecks of diamond costing pennies per gram could be used as sensors because, says Budker, "we can control the number of NV centers in the diamond just by irradiating and baking it," that is, annealing it.

The challenge is to keep the information inherent in the spin states of NV centers, once it has been encoded there, from leaking away before measurements can be performed; in NV centers, this requires extending what's called the "coherence" time of the electron spins, the time the spins remain synchronized with each other.

Recently Budker worked with Ronald Walsworth of Harvard in a team that included Harvard's Nir Bar-Gill and UC Berkeley postdoc Andrey Jarmola. They extended the coherence time of an ensemble of NV electron spins by more than two orders of magnitude over previous measurements.

"To me, the most exciting aspect of this result is the possibility of studying changes in the way NV centers interact with one another," says Bar-Gill, the first author of the paper, who will move to Hebrew University in Jerusalem this fall. "This is possible because the coherence times are much longer than the time needed for interactions between NV centers."

Bar-Gill adds, "We can now imagine engineering diamond samples to realize quantum computing architectures." The interacting NV centers take the role of bits in quantum computers, called qubits. Whereas a binary digit is either a 1 or a 0, a qubit represents a 1 and a 0 superposed, a state of Schrödinger's-cat-like simultaneity that persists as long as the states are coherent, until a measurement is made that collapses all the entangled qubits at once.

"We used a couple of tricks to get rid of sources of decoherence," says Budker. "One was to use diamond samples specially prepared to be pure carbon-12." Natural diamond includes a small amount of the isotope carbon-13, whose nuclear spin hurries the decoherence of the NV center electron spins. Carbon-12 nuclei are spin zero.

"The other trick was to lower the temperature to the temperature of liquid nitrogen," Budker says. Decoherence was reduced by cooling the samples to 77 degrees Kelvin, below room temperature but still readily accessible.

Working together in Budker's lab, members of the team mounted the diamond samples inside a cryostat. A laser beam passing through the diamond, plus a magnetic field, tuned the electron spins of the NV centers and caused them to fluoresce. Their fluorescent brightness was a measure of spin-state coherence.

"Controlling the spin is essential," Budker says, "so we borrowed an idea from nuclear magnetic resonance" - the basis for such familiar procedures as magnetic resonance imaging (MRI) in hospitals.

While different from nuclear spin, electron spin coherence can be extended with similar techniques. Thus, as the spin states of the NV centers in the diamond sample were about to decohere, the experimenters jolted the diamond with a series of up to 10,000 short microwave pulses. The pulses flipped the electron spins as they began to fall out of synchronization with one another, producing "echoes" in which the reversed spins caught up with themselves. Coherence was reestablished.

Eventually the researchers achieved spin coherence times lasting over half a second. "Our results really shine for magnetic field sensing and for quantum information," says Bar-Gill.

Long spin-coherence times add to the advantages diamond already possesses, putting diamond NVs at the forefront of potential candidates for practical quantum computers - a favorite pursuit of the Harvard researchers. What Budker's group finds an even hotter prospect is the potential for long coherence times in sensing oscillating magnetic fields, with applications ranging from biophysics to defense.

This work was supported by the Defense Advanced Research Projects Agency's QuASAR program, the National Science Foundation, the Israeli Ministry of Defense, and the North Atlantic Treaty Organization's Science for Peace Program.

####

About Berkeley Lab
Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit www.lbl.gov.

For more information, please click here

Contacts:
Paul Preuss

510-486-6249

Copyright © Berkeley Lab

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 Links

“Solid-state electronic spin coherence time approaching one second,” by Nir Bar-Gill, Linh M. Pham, Andrey Jarmola, Dmitry Budker, and Ronald L. Walsworth, appears in the 23 April 2013 edition of Nature Communications, online at:

Related News Press

News and information

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Laboratories

Giving batteries a longer life with the Advanced Photon Source: New research uncovers a hydrogen-centered mechanism that triggers degradation in the lithium-ion batteries that power electric vehicles September 13th, 2024

A 2D device for quantum cooling:EPFL engineers have created a device that can efficiently convert heat into electrical voltage at temperatures lower than that of outer space. The innovation could help overcome a significant obstacle to the advancement of quantum computing technol July 5th, 2024

A battery’s hopping ions remember where they’ve been: Seen in atomic detail, the seemingly smooth flow of ions through a battery’s electrolyte is surprisingly complicated February 16th, 2024

NRL discovers two-dimensional waveguides February 16th, 2024

Brain-Computer Interfaces

Developing nanoprobes to detect neurotransmitters in the brain: Researchers synthesize fluorescent molecularly imprinted polymer nanoparticles to sense small neurotransmitter molecules and understand how they govern brain activity March 3rd, 2023

Taking salt out of the water equation October 7th, 2022

Development of dendritic-network-implementable artificial neurofiber transistors: Transistors with a fibrous architecture similar to those of neurons are capable of forming artificial neural networks. Fibrous networks can be used in smart wearable devices and robots September 24th, 2021

New brain-like computing device simulates human learning: Researchers conditioned device to learn by association, like Pavlov's dog April 30th, 2021

Govt.-Legislation/Regulation/Funding/Policy

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Institute for Nanoscience hosts annual proposal planning meeting May 16th, 2025

Rice researchers harness gravity to create low-cost device for rapid cell analysis February 28th, 2025

Spintronics

An earth-abundant mineral for sustainable spintronics: Iron-rich hematite, commonly found in rocks and soil, turns out to have magnetic properties that make it a promising material for ultrafast next-generation computing April 25th, 2025

‘Brand new physics’ for next generation spintronics: Physicists discover a unique quantum behavior that offers a new way to manipulate electron-spin and magnetization to push forward cutting-edge spintronic technologies, like computing that mimics the human brain January 17th, 2025

Researchers discover a potential application of unwanted electronic noise in semiconductors: Random telegraph noises in vanadium-doped tungsten diselenide can be tuned with voltage polarity August 11th, 2023

Quantum materials: Electron spin measured for the first time June 9th, 2023

Quantum Computing

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

Magnetism in new exotic material opens the way for robust quantum computers June 4th, 2025

A new study provides insights into cleaning up noise in quantum entanglement:When it comes to purifying quantum entanglement, new theoretical work highlights the importance of tailoring noise-minimizing solutions to specific quantum systems May 16th, 2025

Programmable electron-induced color router array May 14th, 2025

Sensors

Quantum sensors tested for next-generation particle physics experiments: New research shows that the specialized sensors can detect particles more precisely April 25th, 2025

Quantum engineers ‘squeeze’ laser frequency combs to make more sensitive gas sensors January 17th, 2025

UCF researcher discovers new technique for infrared “color” detection and imaging: The new specialized tunable detection and imaging technique for infrared photons surpasses present technology and may be a cost-effective method of capturing thermal imaging or night vision, medica December 13th, 2024

Nanotechnology: Flexible biosensors with modular design November 8th, 2024

Discoveries

Researchers unveil a groundbreaking clay-based solution to capture carbon dioxide and combat climate change June 6th, 2025

Cambridge chemists discover simple way to build bigger molecules – one carbon at a time June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Announcements

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Homeland Security

The picture of health: Virginia Tech researchers enhance bioimaging and sensing with quantum photonics June 30th, 2023

Sensors developed at URI can identify threats at the molecular level: More sensitive than a dog's nose and the sensors don't get tired May 21st, 2021

UCF researchers generate attosecond light from industrial laser: The ultrafast measurement of the motion of electrons inside atoms, molecules and solids at their natural time scale is known as attosecond science and could have important implications in power generation, chemical- August 25th, 2020

Highly sensitive dopamine detector uses 2D materials August 7th, 2020

Military

Quantum engineers ‘squeeze’ laser frequency combs to make more sensitive gas sensors January 17th, 2025

Chainmail-like material could be the future of armor: First 2D mechanically interlocked polymer exhibits exceptional flexibility and strength January 17th, 2025

Single atoms show their true color July 5th, 2024

NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024

Energy

Portable Raman analyzer detects hydrogen leaks from a distance: Device senses tiny concentration changes of hydrogen in ambient air, offering a dependable way to detect and locate leaks in pipelines and industrial systems April 25th, 2025

KAIST researchers introduce new and improved, next-generation perovskite solar cell​ November 8th, 2024

Unveiling the power of hot carriers in plasmonic nanostructures August 16th, 2024

Groundbreaking precision in single-molecule optoelectronics August 16th, 2024

Research partnerships

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Superconductors: Amazingly orderly disorder: A surprising effect was discovered through a collaborative effort by researchers from TU Wien and institutions in Croatia, France, Poland, Singapore, Switzerland, and the US during the investigation of a special material: the atoms are May 14th, 2025

HKU physicists uncover hidden order in the quantum world through deconfined quantum critical points April 25th, 2025

SMART researchers pioneer first-of-its-kind nanosensor for real-time iron detection in plants February 28th, 2025

Quantum nanoscience

A new study provides insights into cleaning up noise in quantum entanglement:When it comes to purifying quantum entanglement, new theoretical work highlights the importance of tailoring noise-minimizing solutions to specific quantum systems May 16th, 2025

Superconductors: Amazingly orderly disorder: A surprising effect was discovered through a collaborative effort by researchers from TU Wien and institutions in Croatia, France, Poland, Singapore, Switzerland, and the US during the investigation of a special material: the atoms are May 14th, 2025

Programmable electron-induced color router array May 14th, 2025

Unraveling the origin of extremely bright quantum emitters: Researchers from Osaka University have discovered the fundamental properties of single-photon emitters at an oxide/semiconductor interface, which could be crucial for scalable quantum technology February 28th, 2025

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