Related Experiment Video
Updated: Jul 4, 2026
10:35
Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
Pendellösung effect in photonic crystals
S Savo1, E Di Gennaro, C Miletto
1CNISM and Department of Physics, Università di Napoli Federico II, Piazzale Tecchio 80, I-80125 Naples, Italy.
Optics Express
|June 12, 2008
Summary
Researchers experimentally observed the Pendellösung phenomenon in microwave photonic crystals. This effect, a periodic energy exchange between direct and diffracted beams, modulates wave intensity based on crystal thickness.
Area of Science:
- Physics
- Electromagnetism
- Materials Science
Background:
- Photonic crystals exhibit unique wave manipulation properties.
- The Pendellösung phenomenon describes energy transfer between coupled wave modes.
Purpose of the Study:
- To experimentally demonstrate the Pendellösung phenomenon in microwave photonic crystals.
- To investigate the influence of slab thickness on diffracted wave intensity.
Main Methods:
- Fabrication of 2D photonic crystal slabs with varying thicknesses.
- Irradiation of slabs with microwaves at approximately 14 GHz.
- Measurement of electromagnetic field intensity distributions at the exit surface and within the crystals.
Main Results:
- Observed periodic modulation of diffracted wave intensity with slab thickness.
- Intensity maxima shifted between forward and negative diffraction directions.
- Confirmed energy exchange between direct and diffracted beams.
Conclusions:
- Experimental validation of the Pendellösung phenomenon in microwave photonic crystals.
- Demonstrated thickness-dependent control over wave propagation and diffraction.
- Potential applications in tunable microwave devices.
Related Concept Videos
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...
01:29Determination of Crystal Structures
In the late 1800s, the revelation that light extended beyond visible wavelengths led to the discovery of X-rays by Wilhelm Roentgen. Recognized as high-energy electromagnetic radiation with short wavelengths, X-rays prompted exploration into their interaction with crystals. Max von Laue proposed in 1912 that the periodic arrangement of atoms, ions, or molecules in crystals would cause them to diffract X-rays, a hypothesis confirmed through experiments with copper sulfate and zinc sulfide...
01:11P-N junction
A p-n junction is formed when p-type and n-type semiconductor materials are joined together. At the interface of the p-n junction, holes from the p-side and electrons from the n-side begin to diffuse into the opposite sides due to the concentration gradient. This diffusion of carriers leads to a region around the junction where there are no free charge carriers, known as the depletion region. The charge density within the depletion region for the n-side and p-side can be described by the...
02:18X-ray Crystallography
The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
01:26Imperfections in Crystal Structure: Stoichiometric Point Defects
Schottky defects arise when some lattice points in a crystal, such as those in NaCl, remain unoccupied, creating lattice vacancies without disturbing the overall electrical neutrality of the crystal. This defect is common in ionic crystals where the positive and negative ions are similar in size, as seen in sodium chloride and cesium chloride. The presence of Schottky defects enables the crystal to conduct electricity to a small extent through an ionic mechanism. Electric fields cause nearby...