Optically written optofluidic ice channels

We demonstrate that a range of liquid channels can be created within ice blocks using light. We show that channels with dimensions as small as 40 νm can be made using a 1064nm laser beam coupled through single-mode fibre. This is in contrast to larger 'tapered' fibres that can be made using multimode fibre and more irregular channels using free space beams. The channels can be stabilized over timescales of minutes using powers as low as 30mW. Furthermore we demonstrate that liquid samples containing particles may be inserted into the channels and present evidence that particles can be trapped and manipulated using a combination of optical and thermal forces within the light-created microchannels. Furthermore we suggest that such techniques could be used to create templates for conventional microfluidic channels.