Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Which qubit my dear? New method to distinguish between neighbouring quantum bits

This is Professor Michelle Simmons, director of the Australian Centre of Excellence for Quantum Computation and Communication Technology.

Credit: UNSW
This is Professor Michelle Simmons, director of the Australian Centre of Excellence for Quantum Computation and Communication Technology.

Credit: UNSW

Abstract:
Researchers at the University of New South Wales have proposed a new way to distinguish between quantum bits that are placed only a few nanometres apart in a silicon chip, taking them a step closer to the construction of a large-scale quantum computer.

Which qubit my dear? New method to distinguish between neighbouring quantum bits

Sydney, Australia | Posted on June 18th, 2013

Quantum bits, or qubits, are the basic building blocks of quantum computers - ultra-powerful devices that will offer enormous advantages for solving complex problems.

Professor Michelle Simmons, leader of the research team, said a qubit based on the spin of an individual electron bound to a phosphorus atom within a silicon chip is one of the most promising systems for building a practical quantum computer, due to silicon's widespread use in the microelectronics industry.

"However, to be able to couple electron-spins on single atom qubits, the qubits need to be placed with atomic precision, within just a few tens of nanometres of each other," she says.

"This poses a technical problem in how to make them, and an operational problem in how to control them independently when they are so close together."

The UNSW team, in collaboration with theorists at Sandia National Laboratories in New Mexico, has found a solution to both these problems. Their study is published in the journal Nature Communications.

In a significant feat of atomic engineering, they were able to read-out the spins of individual electrons on a cluster of phosphorus atoms that had been placed precisely in silicon. They also propose a new method for distinguishing between neighbouring qubits that are only a few nanometres apart.

"It is a daunting challenge to rotate the spin of each qubit individually," says Holger Büch, lead author of the new study.




"If each electron spin-qubit is hosted by a single phosphorus atom, every time you try to rotate one qubit, all the neighbouring qubits will rotate at the same time - and quantum computation will not work. "

"But if each electron is hosted by a different number of phosphorus atoms, then the qubits will respond to different electromagnetic fields - and each qubit can be distinguished from the others around it," he says.

The UNSW team is part of the Australian Centre of Excellence for Quantum Computation and Communication Technology, a world-leading research centre headquartered in Sydney, Australia.

"This is an elegant and satisfying piece of work," says Professor Simmons, centre director and Mr Büch's PhD supervisor. "This first demonstration that we can maintain long spin lifetimes of electrons on multi-donor systems is very powerful. It offers a new method for addressing individual qubits, putting us one step closer to realising a practical, large-scale quantum computer."

To make the tiny device, the researchers deposited a layer of hydrogen on a silicon wafer and used a scanning tunnelling microscope to create a pattern on the surface in an ultra-high vacuum.

This was then exposed to phosphine gas and annealed at 350 degrees so phosphorus atoms became incorporated precisely into the silicon. The device was then buried in another layer of silicon.

In a quantum computer information is stored in the spin, or magnetic orientation, of an electron. This spin can not only be in two states - up and down - just as in a classical computer.

It can also be in a combination of both states at the same time, allowing exponentially larger amounts of information to be stored and processed in parallel.

####

For more information, please click here

Contacts:
Professor Michelle Simmons:

+ 61 (2) 9385 6313

UNSW Science media:
Deborah Smith

61-293-857-307

Copyright © University of New South Wales

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

PetLife Comments on CNN Story on Scorpion Venom Health Benefits August 27th, 2014

Nanodiamonds Are Forever: A UCSB professor’s research examines 13,000-year-old nanodiamonds from multiple locations across three continents August 27th, 2014

Aspen Aerogels, Inc. to Present at Barclays CEO Energy-Power Conference August 27th, 2014

Nanotech Security Corp. to Acquire Fortress Optical Features Ltd., a Leading Producer of Banknote Security Features August 27th, 2014

Imaging

JPK expands availability of instrumentation in the USA – appointing new distributors – launched a new web site to support the US market - AFM now available to US users August 26th, 2014

Scientists craft atomically seamless, thinnest-possible semiconductor junctions August 26th, 2014

X-ray Laser Probes Tiny Quantum Tornadoes in Superfluid Droplets: SLAC Experiment Reveals Mysterious Order in Liquid Helium August 25th, 2014

Biomimetic photodetector 'sees' in color: Rice lab uses CMOS-compatible aluminum for on-chip color detection August 25th, 2014

Physics

Creation of a Highly Efficient Technique to Develop Low-Friction Materials Which Are Drawing Attention in Association with Energy Issues August 26th, 2014

X-ray Laser Probes Tiny Quantum Tornadoes in Superfluid Droplets: SLAC Experiment Reveals Mysterious Order in Liquid Helium August 25th, 2014

Spintronics

Molecular engineers record an electron's quantum behavior August 14th, 2014

Diamond defect interior design: Planting imperfections called 'NV centers' at specific spots within a diamond lattice could advance quantum computing and atomic-scale measurement August 5th, 2014

University of Illinois study advances limits for ultrafast nano-devices July 10th, 2014

Harnessing magnetic vortices for making nanoscale antennas: Scientists explore ways to synchronize spins for more powerful nanoscale electronic devices April 30th, 2014

Chip Technology

Scientists craft atomically seamless, thinnest-possible semiconductor junctions August 26th, 2014

RMIT delivers $30m boost to micro and nano-tech August 26th, 2014

Competition for Graphene: Berkeley Lab Researchers Demonstrate Ultrafast Charge Transfer in New Family of 2D Semiconductors August 26th, 2014

Symphony of nanoplasmonic and optical resonators leads to magnificent laser-like light emission August 26th, 2014

Quantum Computing

Molecular engineers record an electron's quantum behavior August 14th, 2014

Diamonds are a Quantum Computer’s Best Friend: A new kind of quantum computer is being proposed by scientists from the TU Wien (Vienna) and Japan (National Institute of Informatics and NTT Basic Research Labs) August 8th, 2014

Diamond defect interior design: Planting imperfections called 'NV centers' at specific spots within a diamond lattice could advance quantum computing and atomic-scale measurement August 5th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

Discoveries

The thunder god vine, assisted by nanotechnology, could shake up future cancer treatment: Targeted therapy for hepatocellular carcinoma using nanotechnology August 27th, 2014

Creation of a Highly Efficient Technique to Develop Low-Friction Materials Which Are Drawing Attention in Association with Energy Issues August 26th, 2014

Competition for Graphene: Berkeley Lab Researchers Demonstrate Ultrafast Charge Transfer in New Family of 2D Semiconductors August 26th, 2014

Symphony of nanoplasmonic and optical resonators leads to magnificent laser-like light emission August 26th, 2014

Announcements

Nanodiamonds Are Forever: A UCSB professor’s research examines 13,000-year-old nanodiamonds from multiple locations across three continents August 27th, 2014

Aspen Aerogels, Inc. to Present at Barclays CEO Energy-Power Conference August 27th, 2014

Nanotech Security Corp. to Acquire Fortress Optical Features Ltd., a Leading Producer of Banknote Security Features August 27th, 2014

Malvern specialists to deliver inaugural short course on polymer characterization at Interplas 2014 August 27th, 2014

Tools

Malvern specialists to deliver inaugural short course on polymer characterization at Interplas 2014 August 27th, 2014

JPK expands availability of instrumentation in the USA – appointing new distributors – launched a new web site to support the US market - AFM now available to US users August 26th, 2014

Scientists craft atomically seamless, thinnest-possible semiconductor junctions August 26th, 2014

RMIT delivers $30m boost to micro and nano-tech August 26th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE