Effects of environmental gas conditions on laser opto-microengine performance

We propose an opto-microengine that acts as a micro-actuator in which optical energy is supplied by a laser beam. The opto-microengine is rotated by molecular gas dynamics effects w1x. The effects of the molecular weights of gases on laser opto-microengine performance are revealed by experiments. Helium, argon, and xenon gases are used as environmental gases for operation of the opto-microengine. The maximum torsion torque and the rotational rate of the engine increase when the molecular weights of the gases decrease. In the case of helium as the environmental gas, it is revealed by the experimental data that the torque and the rotational rate are the highest. The direct simulation Monte Carlo DSMC.method numerically simulates gas molecular motions around the opto-microengine. The numerical results show that pressure differences between front and back surfaces of the rotor blade depend on the molecular weights of the gases. It is shown that the torque increases with decreasing molecular weights of the gases. q1999 Elsevier Science B.V. All rights reserved.