Subscribe to our free daily newsletters
. 24/7 Space News .




Subscribe to our free daily newsletters



TIME AND SPACE
A bit of a 'quantum magic trick'
by Staff Writers
St. Louis MO (SPX) Nov 06, 2017


illustration only

An accurate analog clock tick-tick-ticks with a constant precision and well known frequency: one tick per second. The longer you let it tick, the better to test its accuracy --10 times as long corresponds to a ten-fold improvement in any frequency uncertainty. But is there a faster way to determine a frequency?

It turns out there is, in a new discovery published this week in Physical Review Letters by a collaboration between a Washington University in St. Louis professor and graduate student along with a University of Rochester researcher.

The speed-up in frequency measurement comes from quantum mechanics. When a quantum bit is used to measure the frequency of a signal, the strange rules of quantum mechanics allow the frequency measurement to be much more accurate. The technique hinges on the ability to put the quantum bit in a superposition of its two quantum states, and then shift these states around in time with the signal.

Kater Murch, assistant professor of physics in Arts and Sciences, along with graduate student Mahdi Naghiloo and theory collaborator Andrew Jordan of Rochester described the technique as a "quantum magic trick."

"It's reminiscent of the magic tricks that involve a ball placed under one of two cups and the cups are shuffled around - except this time, the ball can be under both cups at the same time," Murch said.

"The resulting speedup in frequency measurement is astonishing. Now, by measuring for 10 times as long, the frequency uncertainty can be reduced by a factor of 100 - enabling enhanced resolution of the frequency beyond any other technique of its kind. Earlier theory work published by the Jordan group this year has proven in two separate papers that the technique applied in this paper is the theoretical optimum that quantum mechanics allows."

The experiment was completed by using a superconducting quantum system where an external oscillating signal with unknown frequency caused the quantum system to undergo periodic changes. By applying quantum pulses on top of the oscillating signal, the state of the system could be controlled so that the final readout of the quantum system became highly sensitive to the precise value of the oscillation frequency.

The underlying physical source of the advantage is related to the fact that the energy of the quantum system is time-dependent, which causes the quantum states corresponding to different frequencies to accelerate away from each other, giving enhanced distinguishability in a given time.

This method permitted enhanced resolution of the frequency beyond any other technique of its kind, Jordan said.

This work is just one example of how the new field of quantum technologies uses the laws of quantum physics for technological advantage over classical physics, Jordan said. Other examples include quantum computing, quantum sensing and quantum simulation. For those fields, the exploitation of quantum physics provides benefits such as a speed up of database search, the factoring of large numbers or the rapid simulation of complex molecules.

Such fine-scale measurement of the frequency of a periodic signal is the fundamental ingredient in diverse applications including MRI medical imaging devices, the analysis of light emitted from stars and, of course, clock precision. Accelerating these measurements in a way that Murch and Jordan have demonstrated could have profound impacts in many areas.

Murch and Naghiloo used timekeeping and GPS, and such constantly advancing technologies, as examples of the importance of their findings.

"Nowadays, most of us carry a phone in our pocket that is capable of telling us almost exactly where we are on Earth using the Global Positioning System," Murch said. "The way this works is that your phone receives signals from several different satellites, and by timing the relative arrival of these signals it infers your position. The accuracy of the timing directly relates to the accuracy of your position - a relationship between timekeeping and navigation that has persisted for hundreds of years.

"Well before GPS, a sailor who wanted to know his location would navigate by the stars. In the Northern Hemisphere, the height of the north star will tell you your latitude, but to know your longitude, you need to keep track of the time. As the night goes on, the stars circle around the north star - the height of any star above the horizon is related to the local time, and by comparing this time to a clock set to Greenwich Mean Time, the time difference gives your longitude."

Nautical timekeeping underscores the vitality of frequency advances.

"In the 1700s, accurate clocks were the main limitation to ocean navigation," Murch said. "The Scilly naval disaster of 1707 - one of the worst disasters in British naval history - was widely blamed on poor navigation, prompting the British government to invest heavily in precise clocks. The resulting chronometers transformed marine navigation and greatly accelerated the age of discovery.

"Advances in timekeeping continue to have profound impact on technology and fundamental science. Quantum tools, such as the quantum speedup in frequency measurement that we discovered, are necessary to push these technologies forward. This is an exciting time for quantum physics because these quantum resources are increasingly leading to practical advantages over traditional measurement approaches."

Research paper

TIME AND SPACE
New confirmation of Einstein's General Theory of Relativity
Daytona Beach FL (SPX) Jun 08, 2017
Albert Einstein predicted that whenever light from a distant star passes by a closer object, gravity acts as a kind of magnifying lens, brightening and bending the distant starlight. Yet, in a 1936 article in the journal Science, he added that because stars are so far apart "there is no hope of observing this phenomenon directly." Now, an international research team directed by Kailash C. ... read more

Related Links
Washington University in St. Louis
Understanding Time and Space


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

TIME AND SPACE
Saudi Arabia to invest $1 billion in Virgin Galactic

Mice, fish and flies: the animals still being sent into space

Dog star: Scientist recalls training Laika for space

The Noah's Ark of animals sent in to space

TIME AND SPACE
Arianespace to launch Embratel Star One D2

Alaska Aerospace Launches Aurora Launch Services Company

Launch your design with Cheops

NASA Selects Studies for Gateway Power and Propulsion Element

TIME AND SPACE
Martian Ridge Brings Out Rover's Color Talents

Next Mars Rover Will Have 23 'Eyes'

In desert of Oman, a gateway to life on Mars

Winters leave marks on Mars' sand dunes

TIME AND SPACE
China's reusable spacecraft to be launched in 2020

Space will see Communist loyalty: Chinese astronaut

China launches three satellites

Mars probe to carry 13 types of payload on 2020 mission

TIME AND SPACE
New Chinese sat comms company awaits approval

Myanmar to launch own satellite system-2 in 2019: vice president

Eutelsat's Airbus-built full electric EUTELSAT 172B satellite reaches geostationary orbit

Turkey, Russia to Enhance Cooperation in the Field of Space Technologies

TIME AND SPACE
New property found in unusual crystalline materials

Radio Pollution Creates Space Shield for Satellites

Guiding the random laser

Small droplets are a surprise: They disappear more slowly than they 'should'

TIME AND SPACE
Evolutionary theory suggests aliens might not look all that alien

'Monster' planet discovery challenges formation theory

Atmospheric beacons guide NASA scientists in search for life

Overlooked Treasure: The First Evidence of Exoplanets

TIME AND SPACE
Juno Aces 8th Science Pass of Jupiter, Names New Project Manager

Jupiter's X-ray auroras pulse independently

Haumea, the most peculiar of Pluto companions, has a ring around it

Ring around a dwarf planet detected




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement