Featured Research

from universities, journals, and other organizations

Towards Quantum Computing: Artificial Atoms Make Microwave Photons Countable

Date:
February 9, 2007
Source:
Yale University
Summary:
Using artificial atoms on a chip, Yale physicists have taken the next step toward quantum computing by demonstrating that the particle nature of microwave photons can now be detected, according to a report spotlighted in the February 1 issue of the journal Nature.

Scanning electron micrograph of an artificial atom (light blue) inside of a transmission line cavity (dark blue). The "atom," composed of over a billion atoms of aluminum, gives a distinct signal for each possible photon number in the cavity. The theoretical prediction (color plot) was verified by these experiments.
Credit: Image Schuster/Yale

Using artificial atoms on a chip, Yale physicists have taken the next step toward quantum computing by demonstrating that the particle nature of microwave photons can now be detected, according to a report spotlighted in the February 1 issue of the journal Nature.

Quantum theories are often considered to apply best to processes that happen on the smallest scale of atoms and molecules. By making artificial atoms larger — to a size that is nearly visible — and using microwaves as the source of energy, the collaborative research from the laboratory of Professor Robert Schoelkopf and the theory group of Professor Steven Girvin in the departments of Applied Physics and Department of Physics at Yale created an electronic circuit that stores and measures individual microwave photons. In the process, they bring quantum mechanics to a larger scale and hope to employ it to build new kinds of quantum machines.

“The radiation from a microwave oven or cell phone does not seem to have much in common with light, but like its visible counterpart, microwaves are made of individual photons,” said Schoelkopf. “A single microwave photon is quite large, extending over one centimeter in length, and yet has one hundred thousand times less energy than even a visible photon. Unlike a camera, which absorbs the light it detects, our measurement preserves the photons for later use.”

“Advances in quantum computing are among the goals of the recently launched Yale Institute of Nanoscience and Quantum Engineering (YINQE), of which Girvin and Schoelkopf are core members,” said Paul Fleury, Dean of Yale Engineering and Director of YINQE. “Such manipulation of single microwave photons is an important step towards realizing a quantum computer, which could exponentially speed up computations of difficult problems in cryptography, quantum physics and chemistry.”

“Much like the children’s game ‘telephone,’ current solid state quantum computing schemes can only make nearest-neighbor interactions. This forces distant quantum bits (qubits) to communicate by passing through many intermediates causing errors,” said lead author David Schuster, a graduate student who completed this work as part of his thesis in January 2007. “Single microwave photons can be used as mobile carriers of quantum information allowing distant qubits to communicate directly, avoiding these problems.”

The measurements they made represent the next step in circuit quantum electrodynamics, a field introduced by the same groups at Yale in 2004 to study quantum optics with microwaves using integrated circuits. According to Girvin, the detector they designed works “as if we made an antenna on an atom.” Their results demonstrate that microwaves are particles because the system gives a response representing a discrete number of interactions of the microwave with the atom.

In addition to circuits, microwaves interact with a variety of physical systems, including atomic spins, molecules, and even nuclei. Single microwave photons can act as a bridge between these naturally occurring quantum systems and fabricated electrical circuits, resulting in a hybrid processor of quantum information. The next phase of the work, according to the authors, is to connect up multiple “atoms”, using the photons to transfer the information between them.

Co-authors on the paper are A. A. Houck, J. A. Schreier, A. Wallraff, J. M. Gambetta, A. Blais, L. Frunzio, J. Majer, B. Johnson and M. H. Devoret who are all affiliated with YINQE. The research was supported by funds from the National Security Agency under the Army Research Office, the National Science Foundation, the W. M. Keck Foundation, a Yale University Quantum Information and Mesoscopic Physics Fellowship and Yale University.

Citation: Nature: 445, 515-518 (February 1, 2007.) doi:10.1038/nature05461 Nature 431, 162-167 (September 9, 2004)


Story Source:

The above story is based on materials provided by Yale University. Note: Materials may be edited for content and length.


Cite This Page:

Yale University. "Towards Quantum Computing: Artificial Atoms Make Microwave Photons Countable." ScienceDaily. ScienceDaily, 9 February 2007. <www.sciencedaily.com/releases/2007/02/070208193301.htm>.
Yale University. (2007, February 9). Towards Quantum Computing: Artificial Atoms Make Microwave Photons Countable. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2007/02/070208193301.htm
Yale University. "Towards Quantum Computing: Artificial Atoms Make Microwave Photons Countable." ScienceDaily. www.sciencedaily.com/releases/2007/02/070208193301.htm (accessed July 22, 2014).

Share This




More Matter & Energy News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Government Approves East Coast Oil Exploration

Government Approves East Coast Oil Exploration

AP (July 18, 2014) The Obama administration approved the use of sonic cannons to discover deposits under the ocean floor by shooting sound waves 100 times louder than a jet engine through waters shared by endangered whales and turtles. (July 18) Video provided by AP
Powered by NewsLook.com
Sunken German U-Boat Clearly Visible For First Time

Sunken German U-Boat Clearly Visible For First Time

Newsy (July 18, 2014) The wreckage of the German submarine U-166 has become clearly visible for the first time since it was discovered in 2001. Video provided by Newsy
Powered by NewsLook.com
Obama: U.S. Must Have "smartest Airports, Best Power Grid"

Obama: U.S. Must Have "smartest Airports, Best Power Grid"

Reuters - US Online Video (July 17, 2014) President Barak Obama stopped by at a lunch counter in Delaware before making remarks about boosting the nation's infrastructure. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com
Crude Oil Prices Bounce Back After Falling Below $100 a Barrel

Crude Oil Prices Bounce Back After Falling Below $100 a Barrel

TheStreet (July 16, 2014) Oil Futures are bouncing back after tumbling below $100 a barrel for the first time since May yesterday. Jeff Grossman is the president of BRG Brokerage and trades at the NYMEX. Grossman tells TheStreet the Middle East is always a concern for oil traders. Oil prices were pushed down in recent weeks on Libya increasing its production. Supply disruptions in Iraq fading also contributed to prices falling. News from China's economic front showing a growth for the second quarter also calmed fears on its slowdown. Jeff Grossman talks to TheStreet's Susannah Lee on this and more on the Energy Department's Energy Information Administration (EIA) report. Video provided by TheStreet
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins