OPTI510R: Photonics. Khanh Kieu College of Optical Sciences, University of Arizona Meinel building R.626

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1 OPTI510R: Photonics Khanh Kieu College of Optical Sciences, University of Arizona Meinel building R.626

2 Important announcements Homework #2 is due Feb. 12 Mid-term exam Feb 28 (open book/notes)

3 Photonics West

4 Photonics West

5 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

6 Notable News: Photonics West

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10 Polarization optics Polarization optics Anisotropic media Index ellipsoid Uniaxial crystal Double refraction Calcite CaCO3 Polarization devices Polarizer Waveplates Faraday effect Isolators Polarization microscope Phase matching Potassium Niobate

11 Polarization optics The polarization of light is determined by the trajectory of the end of the electric vector in time at a given position.

12 Polarization optics Plastic spoons and folks Thin slide of a meteorite

13 Polarization optics Polarization multiplexing: multiply bit-rate Terabit-Scale Orbital Angular Momentum Mode Division Multiplexing in Fibers, Science 2013

14 Polarization optics Plane wave propagating in the z direction: Where: (A: complex envelope) describes an ellipse (z = const)

15 Some useful formulae

16 Polarization optics Plane wave propagating in the z direction: Where: describes an ellipse (z = const)

17 Polarization optics (Homework)

18 Linear polarization a x or a y = 0 or: = 0 or Plane polarization

19 Circular polarization a x = a y = + /2 a x = a y = - /2

20 Poincaré sphere

21 Other representations Stokes parameters: Jones vector:

22 Anisotropic media Propagation of light depends on the propagation direction!

23 Isotropic media n is a number for isotropic materials such as gas, glass, cubic crystal etc. e r is material relative permittivity m r is material relative permeability, ~ 1 for nonmagnetic material Polarization density, P, is proportional to E, c is electric susceptibility n e n c / P n r v m r ce E 0 1 c glass cubic crystal

24 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)

25 Anisotropic media Index ellipsoid (representation of the tensor):

26 Uniaxial crystals Calcite, Rutile TiO2, Yttrium Vanadate

27 Uniaxial crystals The direction of energy flow is not the same as the wave front propagation direction Double refraction

28 Polarization devices Polarizer: Glan-Thompson polarizer Dichroic polarizer (Stretched Polyvinyl Alcohol (PVA) Double refraction polarizer Glan-Thompson polarizer (Polarization extinction ratio: PER)

29 Polarizer Nichol prism Glan-Foucault prism Beam-displacement prism polarizer Wollaston prism polarizer

30 Waveplates 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) Linearly polarized light decomposes into two components: parallel (green) and perpendicular (blue). Green travels slower and is delay by half wavelength.

31 Waveplates = 90 degree Turn plane polarized light into circularly polarized light and vice versa

32 Faraday effect 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. Wikipedia.org

33 Faraday effect 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. Brain waves magnetometer (NIST) Wikipedia.org

34 Isolators

35 Isolators

36 Polarization microscope

37 Phase matching Second harmonic generation Input IR beam Phase matching concept LBO crystal Angle and Wavelength Dependence of Refractive index of BBO

38 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?