Nav: Home

First demonstration of antimatter wave interferometry

May 03, 2019

Matter waves constitute a crucial feature of quantum mechanics, where particles have wave properties in addition to particle characteristics. This wave-particle duality was postulated already in 1924 by the French physicist Louis de Broglie. The existence of the wave property of matter has been successfully demonstrated in a number of experiments with electrons and neutrons, as well as with more complex matter, up to large molecules. For antimatter the wave-particle duality had also been proven through diffraction experiments. However, researchers of the QUPLAS collaboration now established the wave behavior in a single positron (antiparticle to the electron) interference experiment. The results are reported in the Science Advances journal.

An experiment already envisaged by Einstein

The QUPLAS scientific collaboration includes researchers from the University of Bern and from the University and Politecnico of Milano. To demonstrate the wave duality of single positrons they performed measurements with a setup similar to the so-called double-slit experiment. This setup was already suggested as a gedankenexperiment by famous physicists like Albert Einstein and Richard Feynman; it is often used in quantum theory to demonstrate the wave nature of particles. In the experiment particles (in this case positrons) are directed from a source to a position sensitive detector. In between there are gratings with patterns of two or more slits which the particles go through. Particles behaving like particles travel in straight lines and would produce a pattern corresponding exactly to the grating. If the particles have a wave nature, a striped interference pattern appears at the detector which is different from the grating. The new pattern is generated by the superposition of the waves emitted by the source and travelling through the grating.

Micrometric resolution

The researchers of the QUPLAS collaboration were able to generate for the first time such an interference pattern from single antimatter particle waves. It was obtained thanks to an innovative period-magnifying Talbot-Lau interferometer coupled to a nuclear emulsion position sensitive detector. "With the nuclear emulsions we are able to determine the impact point of individual positrons very precisely which allows us to reconstruct their interferometric pattern with micrometric accuracy - thus to better than millionth of a meter", explains Dr. Ciro Pistillo of the Laboratory of High Energy Physics (LHEP) and Albert Einstein Center (AEC) of the University of Bern. This feature allowed the researchers to overcome the main limitations of antimatter experiments, namely low antiparticle flux and beam manipulation complexity.

The scientists of LHEP and AEC played a key role for the success of the project: Akitaka Ariga, Antonio Ereditato, Ciro Pistillo and Paola Scampoli were in particular responsible for the design, construction and operations of the emulsion detector and for the analysis of positron interaction data.

New field of investigations of antimatter

"Our observation of the energy dependence of interference pattern proves its quantum-mechanical origin and thus the wave nature of the positrons", says Professor Paola Scampoli. The success of the experiment paves the way to a new field of investigations based on antimatter interferometry. A goal is for example to perform gravity measurements with exotic matter-antimatter symmetric atoms such as positronium. With this one could test the validity of the Weak Equivalence Principle for antimatter. This principle is at the basis of general relativity and has never been tested with antimatter. Future research fields based on antimatter interferometry could in the future provide information about the imbalance of matter and antimatter in the universe.
-end-


University of Bern

Related Antimatter Articles:

APS tip sheet: Origins of matter and antimatter
Study suggests an 'axiogenesis' mechanism for the explanation of the matter to antimatter ratio in the Universe
The axion solves three mysteries of the universe
A hypothetical particle called the axion could solve one of physics' great mysteries: the excess of matter over antimatter, or why we're here at all.
NASA's Fermi Mission links nearby pulsar's gamma-ray 'halo' to antimatter puzzle
NASA's Fermi Gamma-ray Space Telescope has discovered a faint but sprawling glow of high-energy light around a nearby pulsar.
Could the mysteries of antimatter and dark matter be linked?
RIKEN researchers and collaborators have performed the first laboratory experiments to determine whether a slightly different way in which matter and antimatter interact with dark matter might be a key to solving both mysteries.
First demonstration of antimatter wave interferometry
An international collaboration with participation of the University of Bern has demonstrated for the first time in an interference experiment that antimatter particles also behave as waves besides having particle properties.
Researchers discover CP violation in charm meson decays
Researchers from the Higher School of Economics and Yandex, as part of the LHCb collaboration at CERN, have been the first to discover CP violation in charm meson decays.
Physicists reveal why matter dominates universe
Physicists in the College of Arts and Sciences at Syracuse University have confirmed that matter and antimatter decay differently for elementary particles containing charmed quarks.
New finding of particle physics may help to explain the absence of antimatter
With the help of computer simulations, particle physics researchers may be able to explain why there is more matter than antimatter in the Universe.
Laser blasting antimatter into existence
Antimatter is an exotic material that vaporizes when it contacts regular matter.
Machine learning improves accuracy of particle identification at LHC
Scientists from the Higher School of Economics have developed a method that allows physicists at the Large Hadron Collider (LHC) to separate between various types of elementary particles with a high degree of accuracy.
More Antimatter News and Antimatter Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Teaching For Better Humans 2.0
More than test scores or good grades–what do kids need for the future? This hour, TED speakers explore how to help children grow into better humans, both during and after this time of crisis. Guests include educators Richard Culatta and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Dispatch 3: Shared Immunity
More than a million people have caught Covid-19, and tens of thousands have died. But thousands more have survived and recovered. A week or so ago (aka, what feels like ten years in corona time) producer Molly Webster learned that many of those survivors possess a kind of superpower: antibodies trained to fight the virus. Not only that, they might be able to pass this power on to the people who are sick with corona, and still in the fight. Today we have the story of an experimental treatment that's popping up all over the country: convalescent plasma transfusion, a century-old procedure that some say may become one of our best weapons against this devastating, new disease.   If you have recovered from Covid-19 and want to donate plasma, national and local donation registries are gearing up to collect blood.  To sign up with the American Red Cross, a national organization that works in local communities, head here.  To find out more about the The National COVID-19 Convalescent Plasma Project, which we spoke about in our episode, including information on clinical trials or plasma donation projects in your community, go here.  And if you are in the greater New York City area, and want to donate convalescent plasma, head over to the New York Blood Center to sign up. Or, register with specific NYC hospitals here.   If you are sick with Covid-19, and are interested in participating in a clinical trial, or are looking for a plasma donor match, check in with your local hospital, university, or blood center for more; you can also find more information on trials at The National COVID-19 Convalescent Plasma Project. And lastly, Tatiana Prowell's tweet that tipped us off is here. This episode was reported by Molly Webster and produced by Pat Walters. Special thanks to Drs. Evan Bloch and Tim Byun, as well as the Albert Einstein College of Medicine.  Support Radiolab today at Radiolab.org/donate.