Polarization scrambling is the process of rapidly varying the
polarization of light within a system using a
polarization controller
A polarization controller is an optical device which allows one to modify the polarization state of light.
Types and operation
Polarization controllers can be operated without feedback, typically by manual adjustment or by electrical signal ...
so that the average polarization over time is effectively randomized. Polarization scrambling can be used in scientific experiments to cancel out errors caused by polarization effects. Polarization scrambling is also used on long-distance fibre optic transmission systems with
optical amplifier
An optical amplifier is a device that amplifies an optical signal directly, without the need to first convert it to an electrical signal. An optical amplifier may be thought of as a laser without an optical cavity, or one in which feedback fr ...
s, in order to avoid
polarization hole-burning
Polarization or polarisation may refer to:
Mathematics
*Polarization of an Abelian variety, in the mathematics of complex manifolds
*Polarization of an algebraic form, a technique for expressing a homogeneous polynomial in a simpler fashion by ...
. Polarization scrambling, also for the variation of
polarization mode dispersion
Polarization mode dispersion (PMD) is a form of modal dispersion where two different polarizations of light in a waveguide, which normally travel at the same speed, travel at different speeds due to random imperfections and asymmetries, causing ...
, is a mandatory test procedure for fiber optic data transmission systems based on
polarization-division multiplexing
Polarization-division multiplexing (PDM) is a physical layer method for multiplexing signals carried on electromagnetic waves, allowing two channels of information to be transmitted on the same carrier frequency by using waves of two orthogonal ...
.
Polarization scramblers usually vary the normalized
Stokes vector
The Stokes parameters are a set of values that describe the polarization state of electromagnetic radiation. They were defined by George Gabriel Stokes in 1852, as a mathematically convenient alternative to the more common description of incoher ...
of the polarization state over the entire
Poincaré sphere Poincaré sphere may refer to:
* Poincaré sphere (optics), a graphical tool for visualizing different types of polarized light
** Bloch sphere, a related tool for representing states of a two-level quantum mechanical system
* Poincaré homology sph ...
. They are commercially available with speeds of 20
Mrad
The Barrett MRAD (Multi-role Adaptive Design) is a bolt-action sniper rifle designed by Barrett to meet the requirements of the SOCOM PSR. The MRAD is based on the Barrett 98B and includes a number of modifications and improvements. The Barrett ...
/s on the Poincaré sphere (see external link). Various speed distributions such as peaked and quasi-Rayleigh can be generated.
Some experiments have implemented ultrafast polarization scrambling on a
polaritonic platform with speeds in the order of the Trad/s on the Poincaré sphere.
See also
*
Depolarizer (optics) A depolarizer or depolariser is an optical device used to scramble the photon polarization, polarization of light. An ideal depolarizer would output randomly polarized light whatever its input, but all practical depolarizers produce pseudo-random ou ...
*
Polarization-division multiplexing
Polarization-division multiplexing (PDM) is a physical layer method for multiplexing signals carried on electromagnetic waves, allowing two channels of information to be transmitted on the same carrier frequency by using waves of two orthogonal ...
*
Polarization controller
A polarization controller is an optical device which allows one to modify the polarization state of light.
Types and operation
Polarization controllers can be operated without feedback, typically by manual adjustment or by electrical signal ...
*
Polarization mixing
References
External links
*
Polarization (waves)
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