Difference between revisions of "Femtosecond Z-Scan Spectrometer"
Cmditradmin (talk | contribs) m (→Significance) |
Cmditradmin (talk | contribs) m (→Significance) |
||
| Line 4: | Line 4: | ||
=== Significance === | === Significance === | ||
The z-scan is based on the self-focusing effect. The index of refraction of a third order material changes as the intensity of the beam changes. As a sample through a focused beam the intensity of incident light increases to a point where the sample changes its index of refraction and alters the focus of the light which can be detected as a change in intensity of light passing through an | The z-scan is based on the self-focusing effect. The index of refraction of a third order material changes as the intensity of the beam changes. As a sample through a focused beam the intensity of incident light increases to a point where the sample changes its index of refraction and alters the focus of the light which can be detected as a change in intensity of light passing through an aperture. | ||
<div id="Flash">Z-Scan Spectrometer</div> | <div id="Flash">Z-Scan Spectrometer</div> | ||
Revision as of 15:23, 14 March 2011
Background
The Femtosecond Z-Scan Spectrometer is used to measure extremely fast non-linear absorption and non-linear refraction. This provides are quick way of the electro-optic coefficient and Kerr non-linearity.
Significance
The z-scan is based on the self-focusing effect. The index of refraction of a third order material changes as the intensity of the beam changes. As a sample through a focused beam the intensity of incident light increases to a point where the sample changes its index of refraction and alters the focus of the light which can be detected as a change in intensity of light passing through an aperture.
In this simulation use the green bar to adjust the z position of the sample in the focused laser beam. The curve is representative of a material with a positive nonlinear refractive index; you'd get a curve with a mirror reflection of this for a negative refractive index material.
<swf width="500" height="400">images/6/69/Z-scan.swf</swf>