Photothermal Excitation for Ultrafast Microfluidic and Nanofluidic Devices

Eric P. Y. Chiou
Mechanical and Aerospace Engineering Department, UCLA

Thursday, September 9, 2010 at 3:00pm
Engr IV Maxwell Room 57-124

Abstract
Short laser pulses with width from nano to femtoseconds have broad applications across wide fields including optical communication, imaging, laser machining, laser surgery, and recently in actuating microfluid and nanofluid devices. It has been shown that a tightly focused laser beam is capable of inducing localized hot plasma for rapid heating and creating cavitation bubbles that expand at speeds up to hundred meters per second in the micro and nanometer scale. Through proper engineering design, such ultrafast actuation mechanism can be spatially patterned and synchronized in time domain to achieve novel microfluidic functions such as ultrafast microfluidic switches and droplet generators. By coupling this photothermal effect with metallic nanostructures, the threshold energy for exciting cavitation bubbles can be greatly reduced and the bubble explosion pattern can be controlled in the nanometer scale. This realizes a novel photothermal nanofluid blade that permits patterned cutting of 3D fragile mammalian cell membranes without strong mechanical support and a platform allowing multiplexed macromolecule delivery into target cells using optical images.

Biography
Prof. Eric P. Y. Chiou received his Ph.D. degree in Electrical Engineering and Computer Sciences Department from the University of California at Berkeley in 2005. He received his M.S. degree in Electrical Engineering Department in the University of California at Los Angeles in 2004 and B.S. degree in Mechanical Engineering Department from National Taiwan University in Taiwan in 1998. He joined the Mechanical and Aerospace Engineering Department at the University of California at Los Angeles in 2006. His research interest is Optical MEMS, BioMEMS, Laser manufacturing, and biophotonics. He has received the NSF CAREER award in 2008.