New research offers an intriguing variation on the famous experiment:
A team of physicists has recreated a classic experiment in particle physics with a dimensional twist, by performing it in time instead of just space. In the process, they showcased the utility of a unique material for future experiments.
The researchers redesigned the double-slit experiment, which was first performed in 1801 and demonstrated a curious trait of light: that it can behave both as a particle and a wave.
The original experiment tested how light moved through space; the recent rendition tested how light would travel if it was only allowed to at specific times. Details of the team's work are published today in Nature Physics.
[...] In the traditional experiment, a beam of light is projected at a barrier, behind which is a photosensitive detector. The barrier has two parallel slits. If you threw ordinary matter at the barrier, they would roughly form the same shape as the slits on the detector. But when light is cast on the slits, it splits into two waves that pass through the barrier and intersect on the other side.
[...] In the new work, the researchers made one big change: They swapped out an ordinary screen with two slits for an indium-tin-oxide film—the same material that is used in modern phone screens. (It's actually a metamaterial, or a material not found in nature, that is engineered to behave a certain way.)
The researchers changed the reflectance of the screen using ultrafast lasers, which only allowed light through at specific times, quadrillionths of a second apart. Basically, they built a quantum tollbooth, using the lasers to create time-dependent slits in the barrier. Even when they only allowed one photon through the screen, the light produced an interference pattern.
Journal Reference:
Tirole, Romain, Vezzoli, Stefano, Galiffi, Emanuele, et al. Double-slit time diffraction at optical frequencies, Nature Physics (DOI: 10.1038/s41567-023-01993-w)
(Score: 3, Interesting) by khallow on Sunday April 09, @04:17PM
(Score: 4, Insightful) by turgid on Sunday April 09, @06:07PM (1 child)
Are neutrons, protons and electrons not "ordinary matter?" Do they not form interference patterns too?
I refuse to engage in a battle of wits with an unarmed opponent [wikipedia.org].
(Score: 1, Informative) by Anonymous Coward on Sunday April 09, @08:40PM
They do, though I think in that sentence they meant more or less "non-quantum" for "ordinary" matter .
(Score: 0) by Anonymous Coward on Sunday April 09, @10:20PM
I think they've successfully reimagined the paradigm.
(Score: 2) by legont on Monday April 10, @03:51AM (1 child)
One photon goes through both slits or they still allow many photons and record a statistical interference picture?
"Wealth is the relentless enemy of understanding" - John Kenneth Galbraith.
(Score: 1) by khallow on Monday April 10, @05:42AM
They measure multiple photons, but they go through the system one at a time. The interference is solely of a photon with itself.
(Score: 2) by VLM on Monday April 10, @05:03PM (1 child)
This is technically unnecessary as people have been doing single photon experiments with PMT tubes "forever".
Its well within technical ability since the 60s to attenuate a light source down to a photon per second and measure and graph the interference pattern one photon at a time.
I'm saying its interesting way to do the experiment, but the physics of single photons interfering with slits is very old.
(Score: 0) by Anonymous Coward on Monday April 10, @05:26PM
It is necessary because it is the whole point of the experiment. The interesting thing here isn't that they are using single photons, it is that they are using single photons and a single slit that opens and closes very close in time. They are making two slits in the temporal axis instead of using the normal two slits in the spatial axis, so in this experiment each individual photon still sees two slits, just this time separated in time. And they still see interference like you do with two slits separated in only space.