OPTI510R: Photonics

Khanh Kieu

College of Optical Sciences,

University of Arizona

kkieu@optics.arizona.edu

Meinel building R.626

Important announcements

Homework #2 is due Feb. 11

Mid-term exam Feb 27, 2PM (open book/notes)

Photonics West

Photonics West

Photonics West

Photonics West is the premier photonics and laser event. With

more than 1,250 companies, this exhibition continues to be the

flagship event to find the latest products, tools, and applications

for your research or business needs.

Over 20,000 registered attendees

1,260 exhibiting companies

more than 4,700 presentations

Symposia on BIOS, LASE, OPTO, MOEMS-MEMS

and Green Photonics

Photonics West

Polarization optics

Polarization optics

Anisotropic media

Index ellipsoid

Uniaxial crystal

Double refraction

Polarization devices

Polarizer

Waveplates

Faraday effect

Isolators

Polarization microscope

Phase matching

Potassium Niobate

Calcite CaCO3

Polarization optics

The polarization of light is determined by the trajectory of the end

of the electric vector in time at a given position.

Polarization optics

Plastic spoons and folks Thin slide of a meteorite

Polarization optics

Polarization multiplexing: multiply bit-rate

Terabit-Scale Orbital Angular Momentum Mode Division

Multiplexing in Fibers,” Science 2013

Polarization optics

Plane wave propagating in the z direction:

Where:

describes an ellipse (z = const)

(A: complex envelope)

Some useful formulae

Polarization optics

Plane wave propagating in the z direction:

Where:

describes an ellipse (z = const)

Polarization optics

(Homework)

Linear polarization

ax or ay = 0

or: = 0 or

Plane polarization

Circular polarization

ax = ay

= +/2

ax = ay

= -/2

Poincaré sphere

Other representations

Stokes parameters:

Jones vector:

Anisotropic media

Propagation of light depends on the propagation direction!

Isotropic media

n is a number for isotropic materials such as

gas, glass, cubic crystal etc.

er is material relative permittivity

mr is material relative permeability, ~ 1 for non-

magnetic material

Polarization density, P, is proportional to E, c is

electric susceptibility

rrn me

vcn /

c

ce

1

0

n

EP

cubic crystalglass

Anisotropic media

The electric permittivity is a matrix (tensor)

D and E may point to different directions

By choice of the coordinate system we can simplify the math:

(Principle refractive index)

Anisotropic media

Index ellipsoid (representation of the tensor):

Uniaxial crystals

Calcite, Rutile TiO2,

Yttrium Vanadate

Uniaxial crystals

The direction of energy flow is not the

same as the wave

front propagation direction

Double refraction

Polarization devices

Polarizer:

Dichroic polarizer (Stretched Polyvinyl Alcohol (PVA)

Double refraction polarizer

Glan-Thompson polarizer

Glan-Thompson polarizer

(Polarization extinction ratio: PER)

Polarizer

Nichol prism

Glan-Foucault prism

Wollaston prism polarizerBeam-displacement prism polarizer

Waveplates

Linearly polarized light decomposes

into two components: parallel (green)

and perpendicular (blue). Green

travels slower and is delay by half

wavelength.

• Usually made of birefringent crystal with extraordinary axis parallel to the surface of the plate and with a carefully chosen thickness

• = 180 degree, use to rotate linear polarization, change right to left circular polarized light (half waveplate)

Waveplates

• = 90 degree

• Turn plane polarized light into circularly polarized light and vice

versa

Faraday effect

Wikipedia.org

β is the angle of rotation (in radians)

B is the magnetic flux density in the direction of

propagation (in teslas)

d is the length of the path (in meters) where the light and

magnetic field interact

is the Verdet constant for the material.

Faraday effect

Wikipedia.org

Brain waves magnetometer

(NIST)

β is the angle of rotation (in radians)

B is the magnetic flux density in the direction of

propagation (in teslas)

d is the length of the path (in meters) where the light and

magnetic field interact

is the Verdet constant for the material.

Isolators

Isolators

Polarization microscope

Phase matching

Phase matching conceptSecond harmonic generation

LBO

crystal

Input IR beam

Angle and Wavelength

Dependence of Refractive

index of BBO

Questions for Thoughts

• Can we explain polarization of light using a theory other than the wave

theory?

• I would like to be at Photonics West, what should I do to get there?

• Do you want to have a booth at Photonics West?

• What are the hottest research areas in optics?

• A new Tucson-based optics company providing polarization devices?