Synopsis: Quantum coherence in cold baths

Spin decoherence is a fundamental obstacle in quantum computation and spintronics. Scientists show they can increase the lifetime of a localized spin in a diamond lattice up to 100 times by polarizing the surrounding spins on the lattice.
Synopsis figure

Nitrogen vacancy centers occur in diamond when a nitrogen atom substitutes for a carbon atom, adjacent to a carbon vacancy. These naturally occurring defects are useful systems in which to study quantum information storage because they possess a localized spin that has a relatively long spin coherence time.

The coherence time of the spin on a nitrogen vacancy center is ultimately limited by fluctuations in its environment (in this case, the fluctuating electron spins on surrounding nitrogen defects). In the current issue of Physical Review Letters, Susumu Takahashi, Ronald Hanson, Johan van Tol, Mark Sherwin, and David Awschalom report they can extend the lifetime of the spin on a nitrogen vacancy center by polarizing the surrounding “spin bath” of nitrogen spins. With electron paramagnetic resonance they estimate that the nitrogen spins are 99.4% polarized in a field of 8 T at 2 K. This very high degree of polarization of the bath lengthens the spin coherence time of the nitrogen vacancy centers by almost two orders of magnitude. - Daniel Ucko


Features

More Features »

Announcements

More Announcements »

Subject Areas

Quantum InformationSpintronics

Previous Synopsis

Gravitation

Post-Minkowski gravity

Read More »

Next Synopsis

Atomic and Molecular Physics

Potassium atoms feel a distant attraction

Read More »

Related Articles

Viewpoint: A Quantum Defect Sees its Charged Surroundings
Magnetism

Viewpoint: A Quantum Defect Sees its Charged Surroundings

Nitrogen-vacancy centers in diamond are found to be more affected by local charge than expected, which has implications for the use of the defects as quantum sensors. Read More »

Focus: Twisted Light in a Photonic Chip
Optics

Focus: Twisted Light in a Photonic Chip

Light waves capable of storing quantum information can propagate through a photonic chip waveguide and potentially be used for on-chip computation. Read More »

Viewpoint: Record Distance for Quantum Cryptography
Optics

Viewpoint: Record Distance for Quantum Cryptography

An optical-fiber-based quantum cryptography scheme works over a record distance of 421 km and at much faster rates than previous long-distance demonstrations. Read More »

More Articles