Related Experiment Video
Updated: Jul 6, 2026
05:52
Observation and Analysis of Blinking Surface-enhanced Raman Scattering
Published on: January 11, 2018
Fractality of light's darkness.
Kevin O'Holleran1, Mark R Dennis, Florian Flossmann
1Department of Physics & Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom. k.oholeran@physics.gla.ac.uk
Physical Review Letters
|March 21, 2008
Summary
Dark lines in natural light fields, known as optical vortices, exhibit fractal properties similar to a random walk. Most vortex lines extend through beams, while others form loops, suggesting universal behavior in random optical fields.
Area of Science:
- Optics and Photonics
- Complex Systems
- Statistical Physics
Background:
- Natural light fields contain dark lines, observable as optical vortices in monochromatic light like laser speckle.
- These optical vortices form lines extending through the entire volume of the light field.
Purpose of the Study:
- To investigate the statistical properties and topological characteristics of optical vortex lines in natural light fields.
- To determine if the behavior of these vortex lines follows predictable mathematical models.
Main Methods:
- Numerical simulations were employed to model light fields and their associated vortex lines.
- Experimental validation was conducted to support the findings from numerical simulations.
Main Results:
- Optical vortex lines were found to possess fractal properties consistent with a Brownian random walk.
- Approximately 73% of vortex lines were observed to percolate through the optical beam, with the remaining forming closed loops.
Conclusions:
- The statistical behavior of optical vortex lines mirrors that of singularities in random discrete lattice models, such as cosmic strings.
- This similarity suggests that the statistics of singularities in random optical fields demonstrate universal behavior across different physical systems.
Related Concept Videos
02:18Interference and Diffraction
Interference is a characteristic phenomenon exhibited by waves. When two electromagnetic waves interact with their peaks and troughs coinciding, a resulting wave with enhanced amplitude is produced. This is known as constructive interference. In this case, the two waves interacting are in phase with each other.
02:12The Wave Nature of Light
The nature of light has been a subject of inquiry since antiquity. In the seventeenth century, Isaac Newton performed experiments with lenses and prisms and was able to demonstrate that white light consists of the individual colors of the rainbow combined together. Newton explained his optics findings in terms of a "corpuscular" view of light, in which light was composed of streams of extremely tiny particles traveling at high speeds according to Newton's laws of motion.
01:19Limits with Oscillating Discontinuities
An oscillating discontinuity is a type of discontinuity in which a function’s values fluctuate infinitely often as the input approaches a particular point. Unlike jump discontinuities, where the function suddenly shifts between two values, or infinite discontinuities, where the function diverges without bound, an oscillating discontinuity arises from rapid back-and-forth variation. Because the function never stabilizes toward a single value, no finite limit exists at that point.One of the most...
02:32The de Broglie Wavelength
In the macroscopic world, objects that are large enough to be seen by the naked eye follow the rules of classical physics. A billiard ball moving on a table will behave like a particle; it will continue traveling in a straight line unless it collides with another ball, or it is acted on by some other force, such as friction. The ball has a well-defined position and velocity or well-defined momentum, p = mv, which is defined by mass m and velocity v at any given moment. This is the typical...
01:16Focusing of Light in the Eye
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
02:26Photoelectric Effect
When light of a particular wavelength strikes a metal surface, electrons are emitted. This is called the photoelectric effect. The minimum frequency of light that can cause such emission of electrons is called the threshold frequency, which is specific to the metal. Light with a frequency lower than the threshold frequency, even if it is of high intensity, cannot initiate the emission of electrons. However, when the frequency is higher than the threshold value, the number of electrons ejected...