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Laboratory of Interfacial & Small Scale Transport
{LIS2T}
About Us
Brief Bio
Prof. Troian moved to the California Institute of Technology in late 2006 from Princeton University, where she was a member of the faculty in the School of Engineering and Applied Science for 13 years. She received her B.A. in Physics from Harvard University in 1980 and her Ph.D in condensed matter theory from Cornell University in 1987, investigating mean field theories of quasicrystal formation with N. David Mermin. From 1987-89 Troian was a postdoctoral researcher with the Complex Fluids Physics Group at Exxon Research & Eng. and from 1989-90 a Chateaubriand Senior Research Fellow working with P. G. de Gennes at the Laboratoire de Physique de la Matière Condensée at the Collège de France in Paris. Upon her return to the US in 1990, she joined Exxon Research as a staff physicist and in 1993 moved to Princeton University. Troian was a recipient of the 1999 Frenkiel Award from the Division of Fluid Dynamics of the American Physical Society and in 2005 was named a Fellow of the APS. During 2004-05, she was in residence at Caltech as a Moore Distinguished Scholar. She is currently Professor of Applied Physics, Aeronautics and Mechanical Engineering specializing in the study of transport phenomena in fluid systems at scales ranging from microns to nanometers.
Prof. Troian moved to the California Institute of Technology in late 2006 from Princeton University, where she was a member of the faculty in the School of Engineering and Applied Science for 13 years. She received her B.A. in Physics from Harvard University in 1980 and her Ph.D in condensed matter theory from Cornell University in 1987, investigating mean field theories of quasicrystal formation with N. David Mermin. From 1987-89 Troian was a postdoctoral researcher with the Complex Fluids Physics Group at Exxon Research & Eng. and from 1989-90 a Chateaubriand Senior Research Fellow working with P. G. de Gennes at the Laboratoire de Physique de la Matière Condensée at the Collège de France in Paris. Upon her return to the US in 1990, she joined Exxon Research as a staff physicist and in 1993 moved to Princeton University. Troian was a recipient of the 1999 Frenkiel Award from the Division of Fluid Dynamics of the American Physical Society and in 2005 was named a Fellow of the APS. During 2004-05, she was in residence at Caltech as a Moore Distinguished Scholar. She is currently Professor of Applied Physics, Aeronautics and Mechanical Engineering specializing in the study of transport phenomena in fluid systems at scales ranging from microns to nanometers.
images:
Top: Interferometric image of an instability triggered by surfactant transport on a 10 µm aqueous film.
Bottom: Microfluidic chip based on thermocapillary actuation. Embedded arrays of Ti microheaters are used to generate thermal surface maps for moving, mixing, splitting and reacting liquid droplets.
Top: Interferometric image of an instability triggered by surfactant transport on a 10 µm aqueous film.
Bottom: Microfluidic chip based on thermocapillary actuation. Embedded arrays of Ti microheaters are used to generate thermal surface maps for moving, mixing, splitting and reacting liquid droplets.
Research Interests
The {LIS2T} research group specializes in the study of micro- and nanoscale transport phenomena in fluidic systems pertinent to many physical, biological, and material flows. Systems confined to these small dimensions manifest large surface to volume ratios and are therefore highly responsive to surface actuation and modulation by tangential and normal forces. During the past decade, we have investigated the influence of boundary geometry and topology, surface forces, competitive transport mechanisms and confinement on the evolution characteristics of moving boundary flows subject to flow instabilities. Of special interest to us are non-linear phenomena triggered by gradients in electric, thermal, concentration or magnetic fields counterbalanced by capillary forces. Over the years, our studies have revealed ways in which spatial and temporal control of gradient fields can be used to enhance, retard, structure or stratify the flow of mass, momentum and energy in small scale systems. In some cases, investigations have elucidated fundamental correlations and scaling laws which arise strictly as a consequence of confinement. In other cases, surface actuation techniques have been exploited for development of miniature sensors and optical arrays for emergent bio-, micro- or optofluidic applications. In addition to these studies, we also have long standing interests in slip phenomena at liquid/solid interfaces as well as the consequences of non-normality and transient growth in linearly unstable systems at low Reynolds number.
In order to explore interfacial phenomena spanning multiple length scales, we typically complement full scale experimentation with analytic work, numerical computations and non-equilibrium molecular dynamics simulations. This combined approach has helped elicit fundamental insights as well as reliable design principles for application driven studies.
{LIS2T} is actively recruiting postdoctoral research associates and (Caltech) graduate research assistants (GRAs) at this time; brief project descriptions can be found above under the tab "Job Openings". Consider joining our eclectic group for some serious fun!
Current research projects
The {LIS2T} research group specializes in the study of micro- and nanoscale transport phenomena in fluidic systems pertinent to many physical, biological, and material flows. Systems confined to these small dimensions manifest large surface to volume ratios and are therefore highly responsive to surface actuation and modulation by tangential and normal forces. During the past decade, we have investigated the influence of boundary geometry and topology, surface forces, competitive transport mechanisms and confinement on the evolution characteristics of moving boundary flows subject to flow instabilities. Of special interest to us are non-linear phenomena triggered by gradients in electric, thermal, concentration or magnetic fields counterbalanced by capillary forces. Over the years, our studies have revealed ways in which spatial and temporal control of gradient fields can be used to enhance, retard, structure or stratify the flow of mass, momentum and energy in small scale systems. In some cases, investigations have elucidated fundamental correlations and scaling laws which arise strictly as a consequence of confinement. In other cases, surface actuation techniques have been exploited for development of miniature sensors and optical arrays for emergent bio-, micro- or optofluidic applications. In addition to these studies, we also have long standing interests in slip phenomena at liquid/solid interfaces as well as the consequences of non-normality and transient growth in linearly unstable systems at low Reynolds number.
In order to explore interfacial phenomena spanning multiple length scales, we typically complement full scale experimentation with analytic work, numerical computations and non-equilibrium molecular dynamics simulations. This combined approach has helped elicit fundamental insights as well as reliable design principles for application driven studies.
{LIS2T} is actively recruiting postdoctoral research associates and (Caltech) graduate research assistants (GRAs) at this time; brief project descriptions can be found above under the tab "Job Openings". Consider joining our eclectic group for some serious fun!
Current research projects
- Thin film evanescent wave sensing for micro/optofluidic devices
- Pattern replication by thermolithography in nanoscale polymer films
- Microfluidic devices based on thermocapillary forces, electrowetting or dielectrophoresis
- Dynamics of free surface flows on topologically modified sustrates
- Biological flows induced by gradient surface forces
- Confinement effects, layering transitions and instabilities in nanoscale liquid films
- Interfacial instabilities triggered by non-normal disturbances
- Characterization of dynamic friction and slip at liquid/solid interfaces
- Molecular versus continuum descriptions of nanoscale film flows
Press Highlights 1999-2009
Article on resist-free patterning of nanofilms by a novel thermocapillary instability:
- Virtual Journal of Nanoscale Science and Technology, Formation of Nanopillar Arrays in Ultrathin Viscous Films: The Critical Role of Thermocapillary Stresses , Vol. 20 (Issue 8), August 24, 2009
- Analytical Chemistry, Diving into Droplets, March 1, 2006 issue, pg. 1401-1404
- Analytical Chemistry: Analytical Currents, Non-intrusive Droplet Analysis, July 2005 issue, pg. 241A
- Virtual Journal of Nanoscale Science and Technology, Influence of boundary slip on the optimal excitations in thermocapillary driven spreading, Vol. 10 (Issue 20), Nov. 15, 2004
- Biochip moves liquids with heat, Technology Research News, April 09, 2003.
- Microfluidics and Jovian Climate, Highlights of DFD Meeting, APS News, Vol. 12, No. 1, January 2003.
- Physics News in 2000 - Biological and Medical Physics (pg 3), Study of thermocapillary flow on micropatterned surfaces cited as one of important physics stories in `00 - APS News, Vol. 20, No. 2, February 2001.
- Microfluidics On the Move: Devices Offer Many Advantages, OE Reports: Technology and Trends for the International Optical Engineering Community, August 2000.
- Microfluidic Technologies on the Rise at DFD Meeting, APS News, Vol. 9, No. 3, March 2000.
- Microfluidic Flows, Physics Today, Physics Update Column, Vol. 53, p. 9 (2000).
- Hot and Cold Chips with Running Fluids, New Scientist, Vol. 164 No. 2215, p. 16 (1999).
- Heat Guides Lab on Chip Flow, Technology Insights - NanoTech Alert, John Wiley & Sons, Dec. 17, 1999.
- TRN News, Process Prints Silicon Circuits, Nov. 5/12, 2003.
- Virtual Journal of Nanoscale Science and Technology, Photoresist-Free Printing of Amorphous Silicon Thin Film Transistors, Vol. 8 (Issue 16), October 2003
- Miniaturization of Offset Printing Down to the Microscale, MRS Spring Meeting 2001, News and Highlights, Tuesday April 17, 2001.
- Coffee Effect Could Benefit Circuit Connections, TRN News, Nov. 2000.
- Continuous Mechanics in Physics Education, by Jerry Gollub, Physics Today, p. 11 (Dec. 2003) [Figure 1].
- A Gallery of Fluid Motion, M. Samimy, K. Breuer, G. Leal and P. Steen, Eds., Cambridge University Press, NY 2004. Our entry in that volume can be viewed by clicking on Streamlets and Branching Dynamics in Surfactant Driven Flows.
Copyright © 2001-2009 Sandra M. Troian. All rights reserved.