Related Experiment Video
Updated: May 31, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Polarization modulation for a stochastic electromagnetic beam passing through a chiral medium.
Fei Zhuang1, Xinyue Du, Daomu Zhao
1Department of Physics and Institute of Condensed Matter Physics, Hangzhou Normal University, Hangzhou 310036, China.
Optics Letters
|July 19, 2011
Summary
We investigated how stochastic electromagnetic beams change when traveling through chiral materials. The study found that beam polarization can be controlled by medium properties and beam coherence, with far-zone polarization differing from the source.
Area of Science:
- Optics and Photonics
- Electromagnetism
- Materials Science
Background:
- Chiral media exhibit unique electromagnetic properties due to their asymmetry.
- Stochastic electromagnetic beams possess random fluctuations in their fields.
- The spectral degree of polarization quantifies the polarization properties of light across different frequencies.
Purpose of the Study:
- To analyze the propagation of stochastic electromagnetic beams in chiral media.
- To investigate the influence of medium chirality and beam coherence on polarization.
- To understand the transformation of polarization properties during beam propagation.
Main Methods:
- Derivation of the cross-spectral density matrix for stochastic electromagnetic beams.
- Calculation of the spectral degree of polarization using the derived matrix.
- Analysis of polarization changes as a function of propagation distance and medium parameters.
Main Results:
- The spectral degree of polarization is significantly modulated by the chiral parameter of the medium.
- Beam coherence parameters effectively control the evolution of the spectral degree of polarization.
- A notable difference exists between the far-zone spectral degree of polarization and that of the source beam.
Conclusions:
- Chiral media offer a means to control the polarization of stochastic electromagnetic beams.
- The study provides insights into the interaction of light with chiral materials.
- Understanding polarization changes is crucial for applications involving light propagation in complex media.
Related Concept Videos
01:29Potential Due to a Polarized Object
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
01:01Group Polarization
Group polarization is the strengthening of an original group attitude following the discussion of views within a group (Teger & Pruitt, 1967). That is, if a group initially favors a viewpoint, after discussion the group consensus is likely a stronger endorsement of the viewpoint. Conversely, if the group was initially opposed to a viewpoint, group discussion would likely lead to stronger opposition.
02:24Properties of Enantiomers and Optical Activity
It is essential to understand the difference between chiral and achiral interactions and the implications thereof in optical activity and their applications. Just as our feet, which are chiral, interact uniquely with chiral objects, such as a pair of shoes, but identically with achiral socks, enantiomers of a molecule exhibit different properties only when they interact with other chiral media. An example of a significant implication from this facet is the phenomenon known as optical activity,...
01:31Dielectric Polarization in a Capacitor
The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...
01:24Potential Due to a Magnetized Object
Magnetic dipoles in magnetic materials are aligned when placed under an external magnetic field. For paramagnets and ferromagnets, dipole alignment occurs in the direction of the magnetic field. However, the dipoles align opposite to the field in the case of diamagnets. This state of magnetic polarization due to the external field is called magnetization. Magnetization is defined as the dipole moment per unit volume. It plays a similar role to polarization in electrostatics.
The vector...
The vector...
01:30Plane Electromagnetic Waves I
The existence of combined electric and magnetic fields that propagate through space as electromagnetic (EM) waves is the most significant prediction of Maxwell's equations. As Maxwell's equations hold in free space, the predicted electromagnetic waves do not require a medium for their propagation. An EM wave comprises an electric field, defined as the force per charge on a stationary charge, and a magnetic field, which is the force per charge on a moving charge.
The EM field is assumed to be a...
The EM field is assumed to be a...