Self-focusing and defocusing of twisted light in non-linear media
Self-focusing and defocusing of twisted light in non-linear media
Self-focusing and defocusing of twisted light in non-linear media
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
From Fig. 1 it is also obvious that the <strong>focus<strong>in</strong>g</strong> effect can be utilized, e.g. for creat<strong>in</strong>g tighter<br />
<strong>and</strong> stronger three-dimensional optical traps by cross<strong>in</strong>g two LG beams at the focused distance.<br />
The predicted <strong>focus<strong>in</strong>g</strong> effect can also be used for the realization <strong>of</strong> more versatile optical<br />
tweezers. From Eq. (22) we <strong>in</strong>fer that to achieve results similar to those <strong>in</strong> Fig. 1 for a smaller<br />
star<strong>in</strong>g waist one has either to <strong>in</strong>crease the <strong>in</strong>tensity (or the frequency) by the roughly the same<br />
amount.<br />
4. Conclusions<br />
We studied the self <strong>focus<strong>in</strong>g</strong> <strong>of</strong> a <strong>twisted</strong> <strong>light</strong> beam <strong>in</strong> a <strong>non</strong>l<strong>in</strong>ear dielectric medium by us<strong>in</strong>g<br />
the paraxial approximation. The differential equation for the beam waist is solved analytically.<br />
The occurrence <strong>of</strong> the focuss<strong>in</strong>g is po<strong>in</strong>ted out <strong>and</strong> its dependence on the beam’s parameters is<br />
worked out analytically <strong>and</strong> illustrated by numerical calculations. Some practical applications<br />
<strong>of</strong> the predicted effect are po<strong>in</strong>ted out.<br />
#135619 - $15.00 USD Received 24 Sep 2010; accepted 31 Oct 2010; published 16 Dec 2010<br />
(C) 2010 OSA 20 December 2010 / Vol. 18, No. 26 / OPTICS EXPRESS 27696
Change language