Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Quantum computing spins closer

Physics graduate student David Press at the optical bench where his current experiments are running.
Physics graduate student David Press at the optical bench where his current experiments are running.

Abstract:
The promise of quantum computing is that it will dramatically outshine traditional computers in tackling certain key problems: searching large databases, factoring large numbers, creating uncrackable codes and simulating the atomic structure of materials.

Quantum computing spins closer

PALO ALTO, CA | Posted on November 22nd, 2008

A quantum step in that direction, if you'll pardon the pun, has been taken by Stanford researchers who announced their success in a paper published in the journal Nature. Working in the Ginzton Laboratory, they've employed ultrafast lasers to set a new speed record for the time it takes to rotate the spin of an individual electron and confirm the spin's new position.

Why does that matter? Existing computers, from laptops to supercomputers, see data as bits of information. Each bit can be either a zero or a one. But a quantum bit can be both zero and one at the same time, a situation known as a superposition state. This allows quantum computers to act like a massively parallel computer in some circumstances, solving problems that are almost impossible for classic computers to handle.

Quantum computing can be accomplished using a property of electrons known as "spin." A single unit of quantum information is the qubit, and can be constructed from a single electron spin, which in this experiment was confined within a nano-sized semiconductor known as a quantum dot.

An electron spin may be described as up or down (a variation of the usual zero and one) and may be manipulated from one state to another. The faster these electrons can be switched, the more quickly numbers can be crunched in a quantum fashion, with its intrinsic advantages over traditional computing designs.

The qubit in the Stanford experiment was manipulated and measured about 100 times faster than with previous techniques, said one of the researchers, David Press, a graduate student in applied physics.

The experiments were conducted at a temperature of almost absolute zero, inside a strong magnetic field produced by a superconducting magnet. The researchers first hit the qubit with laser light of specific frequencies to define and measure the electron spin, all within a few nanoseconds. Then they rotated the spin with polarized light pulses in a few tens of picoseconds (a picosecond is one trillionth of a second). Finally, the spin state was read out with yet another optical pulse.

Similar experiments have been done before, but with radio-frequency pulses, which are slower than laser-light pulses. "The optics were quite tricky," Press said. The researchers had to find a single, specific photon emitted from the qubit in order confirm the spin state of the electron. That photon, however, was clouded in a sea of scattered photons from the lasers themselves.

"The big benefit is to make quantum computing faster," Press said. The experiment "pushed quantum dots up to speed with other qubit candidate systems to ultimately build a quantum computer."

Quantum computers are still years away. In the shorter term, Press said, researchers would like to build a system of tens or hundreds of qubits to simulate the operation of a larger quantum system.

The other authors of the Nature paper were Bingyang Zhang of the Ginzton Lab, and Thaddeus Ladd and Yoshihisa Yamamoto of the Ginzton Lab and the National Institute of Informatics in Tokyo.

####

For more information, please click here

Contacts:

Stanford News Service
425 Santa Teresa St.
Stanford, CA 94305-2245

(650) 723-2558 (main number)
(650) 725-0247 (fax)

Copyright © Stanford University

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

In IEDM 2016 Keynote, Leti CEO Says ‘Hyperconnectivity’, Human-focused Research and the IOT Promise Profound, Positive Changes December 7th, 2016

Leti IEDM 2016 Paper Clarifies Correlation between Endurance, Window Margin and Retention in RRAM for First Time: Paper Presented at IEDM 2016 Offers Ways to Reconcile High-cycling Requirements and Instability at High Temperatures in Resistive RAM December 6th, 2016

Tokyo Institute of Technology research: 3D solutions to energy savings in silicon power transistors December 6th, 2016

Physicists decipher electronic properties of materials in work that may change transistors December 6th, 2016

Spintronics

Making spintronic neurons sing in unison November 18th, 2016

Scientists find technique to improve carbon superlattices for quantum electronic devices: In a paradigm shift from conventional electronic devices, exploiting the quantum properties of superlattices holds the promise of developing new technologies October 20th, 2016

A new spin on superconductivity: Harvard physicists pass spin information through a superconductor October 16th, 2016

NREL discovery creates future opportunity in quantum computing: Research into perovskites looks beyond material's usage for efficient solar cells September 9th, 2016

Quantum Computing

Construction of practical quantum computers radically simplified: Scientists invent ground-breaking new method that puts quantum computers within reach December 5th, 2016

Shape matters when light meets atom: Mapping the interaction of a single atom with a single photon may inform design of quantum devices December 4th, 2016

Single photon converter -- a key component of quantum internet November 28th, 2016

Leti and Grenoble Partners Demonstrate World’s 1st Qubit Device Fabricated in CMOS Process: Paper by Leti, Inac and University of Grenoble Alpes Published in Nature Communications November 28th, 2016

Discoveries

Leti IEDM 2016 Paper Clarifies Correlation between Endurance, Window Margin and Retention in RRAM for First Time: Paper Presented at IEDM 2016 Offers Ways to Reconcile High-cycling Requirements and Instability at High Temperatures in Resistive RAM December 6th, 2016

Tokyo Institute of Technology research: 3D solutions to energy savings in silicon power transistors December 6th, 2016

Physicists decipher electronic properties of materials in work that may change transistors December 6th, 2016

Fast, efficient sperm tails inspire nanobiotechnology December 5th, 2016

Announcements

In IEDM 2016 Keynote, Leti CEO Says ‘Hyperconnectivity’, Human-focused Research and the IOT Promise Profound, Positive Changes December 7th, 2016

Leti IEDM 2016 Paper Clarifies Correlation between Endurance, Window Margin and Retention in RRAM for First Time: Paper Presented at IEDM 2016 Offers Ways to Reconcile High-cycling Requirements and Instability at High Temperatures in Resistive RAM December 6th, 2016

Tokyo Institute of Technology research: 3D solutions to energy savings in silicon power transistors December 6th, 2016

Physicists decipher electronic properties of materials in work that may change transistors December 6th, 2016

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project