Laser driven micro-machine elements

Summary form only given. Production of working micro-machines has motivated research into the fabrication of micro-devices, surface engineering of substrates, and driving mechanisms for micromachines. It has been suggested that optical angular momentum transferred to absorbing or birefringent particles could be harnessed to drive a micro-machine. We describe the trapping and rotation of a microscopic birefringent particle, and show that a spinning fragment of such a material can exert torque on a micro-fabricated structure, through a fluid interface. The spinning birefringent particle and micro-fabricated structure constitute the elements of an optically powered micro-machine.