Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > UCSB Researchers Make Milestone Discovery in Quantum Mechanics

A close-up of one of the circuits used in the quantum mechanics experiment.
A close-up of one of the circuits used in the quantum mechanics experiment.

Abstract:
Researchers at UC Santa Barbara have recently reached what they are calling a milestone in experimental quantum mechanics.

UCSB Researchers Make Milestone Discovery in Quantum Mechanics

Santa Barbara, CA | Posted on August 5th, 2008

In a paper published in the July 17 issue of the journal Nature, UCSB physicists Max Hofheinz, John Martinis, and Andrew Cleland documented how they used a superconducting electronic circuit known as a Josephson phase qubit, developed in Martinis's lab, to controllably pump microwave photons, one at a time, into a superconducting microwave resonator.

Up to six photons were pumped into and stored in the resonator, and their presence was then detected using the qubit, which acts like an electronic atom, as an analyzer. The photon number states, known as Fock states, have never before been controllably created, said Cleland.

"These states are ones you learn about in introductory quantum mechanics classes, but no one has been able to controllably create them before," Cleland said.

Using the same technique, the researchers also created another type of special state, known as a coherent state, in the superconducting resonator. These states are relatively easily generated, and appear to behave in a completely non-quantum mechanical fashion, but by using the same analysis technique, the UCSB researchers were able to demonstrate the expected underlying quantum behavior.

Hofheinz, a postdoctoral researcher from Germany who's been at UCSB for the past year working on this project, explained how the resonator works.

"The resonator is the electrical equivalent of a pendulum," Hofheinz said. "In quantum mechanics the energy, or amplitude of motion of this pendulum, only comes in finite steps, in quanta. We first carefully prepared the resonator in these quantum states, and showed we could do this controllably and then measure the states. Then we ‘kicked' the pendulum directly, a method where the amplitude can take on any value, and appears to not be limited to these quanta. But when we look at the resonator with our qubit, we see that the amplitude does come in steps, but that the resonator is actually in several such states at the same time, so that on average it looks like it is not limited to the quantum states."

Hofheinz spent several months in the UCSB Nanofabrication cleanroom fabricating the device used for the experiment. "This resonator, once you excite it, has to 'swing' for a very long time," he explained. "The first samples I fabricated stopped oscillating very quickly. We had to work to rearrange the fabrication method to get the resonator to oscillate longer."

He then fine-tuned the microwave electronics built by Martinis's group to emit the precisely shaped signals necessary to produce these exciting results.

Martinis, Cleland, and Hofheinz say that their research could help in the quest to build a possible quantum computer, which both the government and industry have been seeking for a long time. A quantum computer could be used to break - or make - the encryption codes most heavily used for secure communication.

"Harmonic oscillators might allow us to get a quantum computer built more quickly," Cleland said.

"I think if they really build one of these quantum computers, there will definitely be resonators in them," Hofheinz said.

####

Contacts:
George Foulsham
805-893-3071


FEATURED RESEARCHERS

Andrew Cleland
805-893-5401


John Martinis
805-893-3910


Max Hofheinz
805-893-5218

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

Graphene holds up under high pressure: Used in filtration membranes, ultrathin material could help make desalination more productive April 24th, 2017

Nanoparticle vaccine shows potential as immunotherapy to fight multiple cancer types April 24th, 2017

Russian scientists create new system of concrete building structures: Sientists of Peter the Great Saint-Petersburg Polytechnic University developed a new construction technology April 24th, 2017

Nanomechanics, Inc. Unveils New Product at ICMCTF Show April 25th: Nanoindentation experts will launch the new Gemini that measures the interaction of two objects that are sliding across each other – not merely making contact April 21st, 2017

Quantum Computing

Harris & Harris Group Issues Its Financial Statements as of December 31, 2016, Posts Its Annual Shareholder Letter, And Will Host a Conference Call for Shareholders on Friday, March 17, 2017 March 15th, 2017

Sorting machine for atoms:Researchers at the University of Bonn clear a further hurdle on the path to creating quantum computers February 10th, 2017

First ever blueprint unveiled to construct a large scale quantum computer February 3rd, 2017

Chiral quantum optics: A new research field with bright perspectives January 31st, 2017

Discoveries

Graphene holds up under high pressure: Used in filtration membranes, ultrathin material could help make desalination more productive April 24th, 2017

Nanoparticle vaccine shows potential as immunotherapy to fight multiple cancer types April 24th, 2017

Russian scientists create new system of concrete building structures: Sientists of Peter the Great Saint-Petersburg Polytechnic University developed a new construction technology April 24th, 2017

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

Announcements

Graphene holds up under high pressure: Used in filtration membranes, ultrathin material could help make desalination more productive April 24th, 2017

Nanoparticle vaccine shows potential as immunotherapy to fight multiple cancer types April 24th, 2017

Russian scientists create new system of concrete building structures: Sientists of Peter the Great Saint-Petersburg Polytechnic University developed a new construction technology April 24th, 2017

Two-dimensional melting of hard spheres experimentally unravelled after 60 years: First definitive experimental evidence of two-dimensional melting of hard spheres April 21st, 2017

Quantum nanoscience

The speed limit for intra-chip communications in microprocessors of the future January 23rd, 2017

First experimental proof of a 70 year old physics theory: First observation of magnetic phase transition in 2-D materials, as predicted by the Nobel winner Onsager in 1943 January 6th, 2017

Quantum simulation technique yields topological soliton state in SSH model January 3rd, 2017

Diamonds are technologists' best friends: Researchers from the Lomonosov Moscow State University have grown needle- and thread-like diamonds and studied their useful properties December 30th, 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