Photonics in random media
In any optical system, distortions to a propagating wavefront reduce the spatial coherence of a light field, making it increasingly difficult to obtain the optimal diffraction-limited spot size. Such aberrations are severely detrimental to optimal performance in imaging, nanosurgery, nanofabrication and micromanipulation, as well as other techniques within modern microscopy. We develop generic methods based on complex optical modulation for true in situ wavefront correction that allows compensation of all aberrations along the entire optical train. The power of the method has been demonstrated for the field of micromanipulation, which is very sensitive to wavefront distortions. We have shown direct trapping with optimally focused laser light carrying power of a fraction of a milliwatt as well as the first trapping through highly turbid and diffusive media. These studies opened up new perspectives for optical micromanipulation in colloidal and biological physics and may be useful for various advanced methods of in-vivo imaging including light-sheet geometries.
T Cizmar, M Mazilu & K Dholakia In situ wavefront correction and its application to micromanipulation. Nature Photonics 4(6) 388-394 (2010)
H Dalgarno, T Cizmar, T Vettenburg, J Nylk, F Gunn-Moore & K Dholakia Wavefront corrected light sheet microscopy in turbid media. Applied Physics Letters 100(19) 191108 (2012)