Optical nonlinearities of tea studied by Z-scan and four-wave mixing techniques

AbstractThird-order non-linearities are important because they allow control over light pulses in ubiquitous high-quality centro-symmetric materials like silicon and silica. Degenerate four-wave mixing provides a direct measure of the third-order non-linear sheet susceptibility χ(3)L (where L represents the material thickness) as well as technological possibilities such as optically gated detection and emission of photons. Using picosecond pulses from a free electron laser, we show that silicon doped with P or Bi has a value of χ(3)L in the THz domain that is higher than that reported for any other material in any wavelength band. The immediate implication of our results is the efficient generation of intense coherent THz light via upconversion (also a χ(3) process), and they open the door to exploitation of non-degenerate mixing and optical nonlinearities beyond the perturbative regime.

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Theoretical and Experimental Studies of Third-Order Nonlinear Optical Susceptibilities of New p-N,N'-Diamethylaniline Tetrathiafulvalene Derivatives

MRS Proceedings ◽

10.1557/proc-660-jj8.25 ◽

2000 ◽

Vol 660 ◽

Cited By ~ 1

Author(s):

B. Sahraoui ◽

K.J. Pluciński ◽

M. Makowaska-Janusik ◽

I. V. Kityk ◽

M. Salle ◽

...

Keyword(s):

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Nonlinear Optical ◽

Experimental Studies ◽

Physical Nature ◽

Four Wave Mixing ◽

Wave Mixing ◽

Electronic Contribution ◽

Optical Nonlinearities ◽

Third Order

ABSTRACTA study was made of third-order nonlinear optical susceptibilities of new tetrathiafulvalene (TTF) derivatives, using the degenerate four wave mixing (DFWM) method, as well as complex quantum chemical calculations. To understand the physical nature of the optical nonlinearities, we separated their electronic and nuclear contributions. We found that the electronic contribution to these nonlinearities predominated. Our investigations suggest that TTF may be a highly promising material for nonlinear optics (NLO).

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Large Cubic Nonlinear Optical Properties of Organic Semiconductor Superlattices

MRS Proceedings ◽

10.1557/proc-173-595 ◽

1989 ◽

Vol 173 ◽

Cited By ~ 1

Author(s):

Samson A. Jenekhe ◽

Wen-Chang Chen ◽

Saukwan Lo ◽

Steven R. Flom

Keyword(s):

Four Wave Mixing ◽

Organic Polymer ◽

Wave Mixing ◽

Optical Nonlinearities ◽

Large Magnitude ◽

Semiconductor Superlattices ◽

Polymer Semiconductor ◽

Device Applications ◽

Further Development ◽

532 Nm

ABSTRACTWe have measured extremely large second hyperpolarizabilities〈γxxxx〉 in solutions of two recently prepared organic polymer semiconductor superlattices. These block copolymers are of alternating aromatic and quinoidal moieties and structurally differ by a side group substituent. The values observed are 1.6 × 10−29 esu for the parent copolymer (PBTBQ) and 3.7 × 10−30 esu for its acetoxy derivative (PBTABQ). The corresponding values of χ(3) are estimated to be 2.7 × 10−7 esu and 4.5 × 108 esu. The measurements, made by picosecond degenerate four wave mixing at 532 nm, showed that the dynamics of the larger χ(3) valued copolymer were faster than the 30 ps resolution of the instrument while the derivative exhibited a slower response. The large magnitude and rapid response of the cubic optical nonlinearities in these novel materials suggest theiT potential for further development and photonic device applications.

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