Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A matterless double-slit

11.01.2010
According to the foundations of quantum mechanics, two different given paths for quantum particles may interfere. Such a so-called "double-slit" scenario is put forward devoid of material constituents, consisting instead entirely of light.

This employs the equally fundamental concept of the structure of quantum vacuum, which mediates between incoming photons from a probe laser and the double-slit formed from two ultra-intense laser pulses (Nature Photonics, 10 Jan 2010).


Figure 1: Two ultra-intense laser pulses (in red) are tightly focused antiparallel to a probe beam (in green). The vacuum current, activated in the interaction regions of the probe and the strong laser fields, generates photons which interfere to produce a diffraction pattern (blue background) with the alternating maxima and minima typical of double-slit experiments.
Photo: MPIK

Double-slits provide incoming particles with a choice. Those that survive the passage have chosen from two possible paths which interfere to distribute them in a wave-like manner. Such wave-particle duality continues to be challenged and investigated in a broad range of disciplines with electrons, neutrons and also biological molecules. All variants of the double-slit experiment have hitherto involved material constituents.

On a seemingly different side, according to quantum electrodynamics virtual electron-positron pairs spontaneously pop into and out of existence in vacuum, on a time scale too short to be directly probed. However, the polarisation of these pairs under an applied electromagnetic field is predicted to support a rich variety of non-linear quantum processes. When driven by a strong electromagnetic field, the virtual electron-positron pairs generate a polarisation and magnetisation in the vacuum and one can form the useful analogy of the polarised quantum vacuum as a solid with non-linear response, which, instead of comprising tangible dipoles, hosts transient polarised virtual particle-antiparticle pairs. Taking the solid-state paradigm one step further, using an ultra-intense laser split into two beams, a nonlinear double-slit can be "activated" by polarising two slit-like regions in the vacuum.

Calculations performed at the Max-Planck-Institute for Nuclear Physics show that when these regions are probed with a second, counter-propagating laser field, one can create the conditions for a real photon-photon double-slit experiment, i. e. a truly quantum double-slit set-up comprising exclusively light. The researchers have simulated the collision of two ultra-intense optical laser beams with a counter-propagating probe field by including the presence of the virtual electrons and positrons in the interaction region. These virtual particles allow the strong fields to scatter the photons of the probe. The scattered photons distribute themselves in a pattern of alternating maxima and minima characteristic of double-slit experiments (Figure 1). This scenario presents on the one hand a realisable method to observe for the first time photon-photon scattering between real photons, and demonstrates on the other, the possibility of both controlling light with light as well as investigating the structure of the quantum vacuum.

Contact:

Dr. Antonino Di Piazza
Max-Planck-Institut für Kernphysik, Heidelberg
Tel: +49-6221-516-171
E-Mail: dipiazza@mpi-hd.mpg.de
Prof. Dr. Christoph H. Keitel
Max-Planck-Institut für Kernphysik, Heidelberg
Tel: +49-6221-516-150
E-Mail: christoph.keitel@mpi-hd.mpg.de

Dr. Bernold Feuerstein | Max-Planck-Gesellschaft
Further information:
http://www.mpi-hd.mpg.de/keitel/
http://www.nature.com/nphoton/journal/vaop/ncurrent/full/nphoton.2009.261.html

More articles from Physics and Astronomy:

nachricht Rapid water formation in diffuse interstellar clouds
25.06.2018 | Max-Planck-Institut für Kernphysik

nachricht When fluid flows almost as fast as light -- with quantum rotation
22.06.2018 | The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Superconducting vortices quantize ordinary metal

Russian researchers together with their French colleagues discovered that a genuine feature of superconductors -- quantum Abrikosov vortices of supercurrent -- can also exist in an ordinary nonsuperconducting metal put into contact with a superconductor. The observation of these vortices provides direct evidence of induced quantum coherence. The pioneering experimental observation was supported by a first-ever numerical model that describes the induced vortices in finer detail.

These fundamental results, published in the journal Nature Communications, enable a better understanding and description of the processes occurring at the...

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Rapid water formation in diffuse interstellar clouds

25.06.2018 | Physics and Astronomy

Using tree-fall patterns to calculate tornado wind speed

25.06.2018 | Earth Sciences

'Stealth' material hides hot objects from infrared eyes

25.06.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>