Del Mar Photonics - Newsletter Winter 2010
Del Mar Photonics supply variety of crystals for THz generation, including ZnTe, GaP, GaSe, LiNbO3 and others
Del Mar Photonics supplies a high quality ZnTe crystals (Zinc Telluride). E-mail us for custom quote or check our online store for items available in stock.
Application notes from Del Mar Photonics customer:
THz generation occurs via optical rectification in a <110> ZnTe. Optical rectification is a difference frequency mixing and occurs in media with large second order susceptibility, c(2). Optical rectification is actually analogous to frequency doubling. That is, a polarization is induced in the crystal that is the difference of the individual frequencies instead of their sum. This is due to the well known trigonometric relation: cos(A) * cos(B) = [cos(A+B) + cos(A-B)] / 2. Thus, light of a given frequency passing through a nonlinear medium will generate the same amount of both sum and difference frequencies, corresponding to second harmonic and dc. Another way of describing these processes is to consider the polarization induced in a medium at frequency 2w when it is driven at frequency w:
|P(2w) = c(2w; w, +w) E(w)E(w)||Frequency doubling|
|P(WTHz) = c(W THz; w, - w) E(w)E(w)||Optical Rectification|
For ultrashort laser pulses that have large bandwidth the frequency components are differenced with each other to produce bandwidth from 0 to several THz. Using either way to describe the process, the generated pulse is the envelope of the optical pulse.
Detection of the THz pulse occurs via free-space electro-optic detection in another <110> oriented ZnTe crystal. The THz pulse and the visible pulse are propagated collinearly through the ZnTe crystal. The THz pulse induces a birefringence in ZnTe crystal which is read out by a linearly polarized visible pulse. When both the visible pulse and the THz pulse are in the crystal at the same time, the visible polarization will be rotated by the THz pulse. Using a l/4 waveplate and a beamsplitting polarizer together with a set of balanced photodiodes, we "map" the THz pulse amplitude by monitoring the visible pulse polarization rotation after the ZnTe crystal at a variety of delay times with respect to the THz pulse.
The ability to read out the full electric field, both amplitude and delay, is one of the attractive features of time-domain THz spectroscopy. Note, the visible and THz pulses are collinearly propagated through the ZnTe crystal even though in the figure they appear to be propagate at an angle.
Related products from Del Mar Photonics
Trestles Pacifica THz Time Domain Spectrometer is a modular tabletop system for scientific and industrial applications of pulsed THz radiation.
New THz band pass and long pass optical filters based on porous silicon and metal mesh technologies
Terahertz products from Del Mar Photonics
GaP crystals fro THz generation
- ZnTe crystals for THz generation
|Photoconductive Antenna for terahertz waves NOTE: All prices are subject to change due to a currency fluctuations! E-mail for quote with current prices.|
ZnTe crystal news and updates
Terahertz pulse generation
Ultrafast E-O Sampling using ZnTe Crystal and Ti:sapphire Laser
Ultrafast sub-ps resolution electro-optic (E-O) sampling system using ZnTe crystal and Ti:sapphire laser
Zinc telluride (ZnTe) crystal structure, lattice parameters
substance: zinc telluride (ZnTe). 26s08d12. property: crystal structure, lattice parameters, thermal expansion. crystal structure: zincblende, space group F
Growth and characterization of <110> oriented ZnTe single crystal
Optical Characterization of ZnTe Single Crystal
THz Generation and Detection in ZnTe
Detection of the THz pulse occurs via free-space electro-optic detection in another <110> oriented ZnTe crystal
Greyhawk Optics - ZnTe crystal, 10x10x0.5 mm, 110-cut
The peak of the THz pulse amplitude shows a three-fold rotational symmetry when the ZnTe detector crystal is rotated by 360░ about an axis normal to the ...
The generation of terahertz (THz) pulses by the optical rectification of femtosecond laser pulses in a ZnTe crystal
Annealing effects of a high-quality ZnTe substrate
Femtosecond Lasers - Reserve a spot in our femtosecond Ti:Sapphire training workshop during this summer in San Diego, California
Trestles femtosecond Ti:Sapphire laser
Trestles Finesse femtosecond Ti:Sapphire laser with integrated DPSS pump laser
Teahupoo Rider femtosecond amplified Ti:Sapphire laser
Mavericks femtosecond Cr:Forsterite laser
Tamarack femtosecond fiber laser (Er-doped fiber)
Buccaneer femtosecond OA fiber laser (Er-doped fiber) and SHG
Cannon Ultra-broadband light source
Tourmaline femtosecond Yt-doped fiber laser