Quantum mechanics runs hot in a cold plasma: research

March 14, 2018, University of British Columbia
Particles quench in a disordered web of quantum interactions to form a state of many-body localization. Credit: Ed Grant

University of British Columbia researchers have found a new system that could help yield 'warmer' quantum technologies.

Quantum technologies such as computers have the potential to process information much more quickly and powerfully than conventional computers. That prospect has spurred interest in exotic, complex quantum phenomena, particularly a state called many-body localization.

Many-body localization occurs when quantum interactions trap particles in a web-like mesh of random locations. This phase of matter protects the energy stored in quantum states from degrading to heat—an effect that could safeguard information in fragile qubits, which are the building blocks of quantum computation.

Up till now efforts to study many-body localization, both theoretically and experimentally, have focussed on cooled to temperatures close to absolute zero, or -273° C. 

"The effect has been assumed to occur only under conditions that are very difficult to engineer," explains UBC chemical physicist Ed Grant. "So far, most evidence for many-body localization has been found using atoms arrayed in space by crossed laser fields. But arrangements like these last only as long as the light is on and are as easily disrupted as ripping a piece of tissue paper."                                                

In the latest issue of Physical Review Letters, Grant and theoretical physicist John Sous describe the results of an experiment in which laser pulses gently lift a large number of molecules in a gas of nitric oxide to form an ultracold plasma.

The plasma, consisting of electrons, ions and Rydberg molecules (NO+ ions orbited by a distant electron), self-assembles and appears to form a robust many-body localized state. The researchers believe the plasma 'quenches' to achieve this state naturally, without needing a web of laser fields - no more ripping apart. 

Just as importantly, the system doesn't have to start at a temperature near absolute zero. The mechanism of self-assembly operates naturally at high temperature, seemingly leading to a spontaneous state of many-body .

"This could give us a much easier way to make a quantum material, which is good news for practical applications," says Grant.

Explore further: Scientists gain new visibility into quantum information transfer

Related Stories

Stirring up a quantum spin-liquid with disorder

December 13, 2017

Disorder is generally thought to be detrimental to creating materials with unusual magnetism or other quantum phenomena. However, a team found that weak disorder surprisingly stabilizes a rare quantum state called a quantum ...

Butterfly emerges from quantum simulation

November 30, 2017

Quantum simulators, which are special-purpose quantum computers, will help researchers identify materials with new and useful properties. This enticing future has just taken a step forward thanks to a collaboration between ...

Quantum computing on the move

November 7, 2017

A future quantum computer, using quantum bits, or qubits, might be able to solve problems that are not tractable for classical computers. Scientists are currently struggling to build devices with more than a few qubits, as ...

Recommended for you

How community structure affects the resilience of a network

June 22, 2018

Network theory is a method for analyzing the connections between nodes in a system. One of the most compelling aspects of network theory is that discoveries related to one field, such as cellular biology, can be abstracted ...

The pho­to­elec­tric ef­fect in stereo

June 22, 2018

In the photoelectric effect, a photon ejects an electron from a material. Researchers at ETH have now used attosecond laser pulses to measure the time evolution of this effect in molecules. From their results they can deduce ...

Water can be very dead, electrically speaking

June 21, 2018

In a study published in Science this week, the researchers describe the dielectric properties of water that is only a few molecules thick. Such water was previously predicted to exhibit a reduced electric response but it ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.