Featured Research

from universities, journals, and other organizations

Mechanical micro-drum used as quantum memory

Date:
March 13, 2013
Source:
National Institute of Standards and Technology (NIST)
Summary:
Researchers have demonstrated that information encoded as a specific point in a traveling microwave signal -- the vertical and horizontal positions of a wave pattern at a certain time -- can be transferred to the mechanical beat of a micro-drum and later retrieved with 65 percent efficiency.

Colorized image of NIST micro-drum and circuit on a sapphire backing. JILA researchers demonstrated that the drum might be used as a memory device in future quantum computers.
Credit: Teufel/NIST

One of the oldest forms of computer memory is back again -- but in a 21st century microscopic device designed by physicists at the National Institute of Standards and Technology (NIST) for possible use in a quantum computer.

The NIST team has demonstrated that information encoded as a specific point in a traveling microwave signal -- the vertical and horizontal positions of a wave pattern at a certain time -- can be transferred to the mechanical beat of a micro-drum and later retrieved with 65 percent efficiency, a good figure for experimental systems like this. The research is described in the March 14 issue of Nature. "We believe the mechanical drum motion could be used as a kind of local memory for quantum information systems," NIST physicist Konrad Lehnert says. "These experiments live at the boundary between classical and quantum systems."

The technique harks back to "delay line memory" that was used in some of the earliest electronic computers, including NIST's own 1950s computer, SEAC. Those devices were fairly simple. They temporarily stored values during computation in the form of acoustic waves traveling down a column of mercury or other fluid. By contrast, the NIST micro-drum memory would exploit a mechanical form of quantum physics.

NIST scientists introduced the micro-drum in 2011. The micro-drum is embedded in a resonant circuit and can beat at different frequencies. By applying microwaves at specific frequencies, researchers can achieve rapid, reliable exchanges between the circuit's electrical energy, in the form of microwave photons (light particles), and the drum's mechanical energy in the form of phonons (units of vibration).

An applied microwave tone can cool the drum down to its lowest-energy ground state, with less than one quantum of energy -- the quantum regime, where the drum can store and convert quantum information. The same interaction transfers information from microwaves in the circuit to the drum, while converting the drum to a temporary state beating at the received frequencies. A key innovation in the latest experiments is the ability to rapidly switch the circuit-drum interactions on and off based on the intensity of the applied microwave tone.

The drum has certain practical advantages as a quantum storage device. Its size and fabrication method are compatible with the devices used for chip-based superconducting quantum bits (qubits), which might be used to represent information in quantum computers. The drum also can retain quantum information for about the same length of time as superconducting circuits can. Quantum computers would rely on the rules of quantum mechanics, nature's rules for the submicroscopic world, to potentially solve important problems that are intractable using today's technology.

In the latest experiments, the quantum information is stored in the amplitude (vertical position) and phase (horizontal position) of the microwave pulse, or waveform, similar to the way some cellular telephones work, Lehnert says. Although this is a classical approach, the experiments are quasi-quantum because the fluctuations, or "noise," in the measurements are quantum mechanical, Lehnert says.

In 8,000 tries, the research team was able to prepare, transfer, store and recapture information 65 percent of the time. This is a good level of efficiency given the early stage of global research on quantum memories; competing quantum memory devices include special crystals and, in nonsolid systems, atomic gases. In the future, researchers plan to combine qubits with the micro-drum, which could serve as either a quantum memory or as an interface between otherwise incompatible systems such as those operating at microwave and optical frequencies. The advance may benefit fundamental physics experiments, quantum information systems and precise force sensing.

The experiments were performed at JILA, a joint institute of NIST and the University of Colorado Boulder, and co-authors include physicists from NIST's Boulder campus. The research was supported by the Defense Advanced Research Projects Agency, the National Science Foundation and NIST.


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology (NIST). Note: Materials may be edited for content and length.


Journal Reference:

  1. T. A. Palomaki, J. W. Harlow, J. D. Teufel, R. W. Simmonds, K. W. Lehnert. Coherent state transfer between itinerant microwave fields and a mechanical oscillator. Nature, 2013; 495 (7440): 210 DOI: 10.1038/nature11915

Cite This Page:

National Institute of Standards and Technology (NIST). "Mechanical micro-drum used as quantum memory." ScienceDaily. ScienceDaily, 13 March 2013. <www.sciencedaily.com/releases/2013/03/130313142528.htm>.
National Institute of Standards and Technology (NIST). (2013, March 13). Mechanical micro-drum used as quantum memory. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2013/03/130313142528.htm
National Institute of Standards and Technology (NIST). "Mechanical micro-drum used as quantum memory." ScienceDaily. www.sciencedaily.com/releases/2013/03/130313142528.htm (accessed October 21, 2014).

Share This



More Matter & Energy News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Newsy (Oct. 21, 2014) If you've ever watched "Back to the Future Part II" and wanted to get your hands on a hoverboard, well, you might soon be in luck. Video provided by Newsy
Powered by NewsLook.com
Robots to Fly Planes Where Humans Can't

Robots to Fly Planes Where Humans Can't

Reuters - Innovations Video Online (Oct. 21, 2014) Researchers in South Korea are developing a robotic pilot that could potentially replace humans in the cockpit. Unlike drones and autopilot programs which are configured for specific aircraft, the robots' humanoid design will allow it to fly any type of plane with no additional sensors. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Graphene Paint Offers Rust-Free Future

Graphene Paint Offers Rust-Free Future

Reuters - Innovations Video Online (Oct. 21, 2014) British scientists have developed a prototype graphene paint that can make coatings which are resistant to liquids, gases, and chemicals. The team says the paint could have a variety of uses, from stopping ships rusting to keeping food fresher for longer. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Portable Breathalyzer Gets You Home Safely

Portable Breathalyzer Gets You Home Safely

Buzz60 (Oct. 21, 2014) Breeze, a portable breathalyzer, gets you home safely by instantly showing your blood alcohol content, and with one tap, lets you call an Uber, a cab or a friend from your contact list to pick you up. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
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:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

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