Experimental Soft Matter
Mechanical Science and Engineering at the University of Illinois


The Juarez group focuses on investigating the fundamental physics behind intruiging phenomena observed in soft matter and living systems.

The two major research themes in our group are
complex fluids, such as polymer solutions, and
active matter, such as bacteria suspensions.

The following subjects are relevant to the problems we like to think about
low Reynolds number fluid mechanics • biophysics • environmental science • rheology • colloid science • polymer physics • microbial ecology

We are part of the Mechanical Science and Engineering Department in the College of Engineering at the University of Illinois.


We are a highly interdisciplinary research team with interests in the field of soft matter. Examples of soft matter include colloidal suspensions, polymer solutions, foams, granular materials, and biological materials. These materials are "soft" in the sense that they are deformed by thermal or mechanical stresses that are comparable to thermal fluctuations at room temperature.

We implement the tools of microfluidics, microscopy, high-speed imaging, and quantitative image analysis to experimentally study problems that lie at the interface of low-Reynolds numbers fluid mechanics, biophysics, and environmental science.

Our approach spans orders of magnitude in length, from single molecules to single cells to the envrionment, and time. We use observations in controlled fluid environments in combination with quantitative image analysis to understand physical mechanisms and chemical processes that we use to build mathematical models and predictive frameworks.

See below for a sample of ongoign and open projects in the lab. See the description of the lab featured in the MechSE department.

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    Oil degradation by marine bacteria

    How do single bacteria rid the oceans of hydrocarbon pollution?
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    Complex fluids and polymer physics

    How do single molecules driven far-from-equilibrium affect material properties such as viscoelasticity?
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    Oil degradation in porous media

    How do physically and chemically heterogeneous microenvironments affect hydrocarbon degradation by bacteria?
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    Cell growth at fluid interfaces

    What is life like when trapped in two dimensions?
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    Particle tracking and microrheology

    How small of a sample is needed to determine its material properties?
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    Microfluidics and imaging techniques

    What new phenomena can we observe using the latest technologies?

Want to learn more?

We are always available and happy to discuss. Visit the lab!

Meet The Team

Gabriel Juarez
Principal Investigator
Member Photo
Sheng Yuan
Graduate student
Topic: Elastic instabilities in polymer solutions
Member Photo
What are you waiting for?
Join now!
See below
Member Photo
Tasty treats?
Lab dog

Interested in joining?

We have openings for creative and highly motivated postdocs, Ph.D., and undergraduate students.

Please send an email
including your qualifications, project of interest,
and CV to gjuarez -at- illinois -dot- edu


  1. Regular and irregular splashing of drops on geometric targets
    G. Juarez, T. Gastopoulos, Y. Zhang, M. L. Siegel and P. E. Arratia
    Physics of Fluids, 24, 091105 (2012)

  2. Splash control of drop impacts with small geometric targets
    G. Juarez, T. Gastopoulos, Y. Zhang, M. L. Siegel and P. E. Arratia
    Physical Review E, 85, 026319 (2012)

  3. Mixing by cutting and shuffling 3D granular flow in spherical tumblers
    G. Juarez, I. C. Christov, J. M. Ottino and R. M. Lueptow
    Chemical Engineering Science, 73, 195-207 (2012)

  4. Extensional rheology of DNA suspensions in microfluidic devices
    G. Juarez and P. E. Arratia
    Soft Matter, 7, 9444 (2011)

  5. Transition to centrifuging granular flow in rotating tumblers: a modified Froude number
    G. Juarez, P. Chen and R. M. Lueptow
    New Journal of Physics, 13, 053055 (2011)

  6. Motility of small nematodes in wet granular media
    G. Juarez, K. Lu, J. Sznitman and P. E. Arratia
    Europhysics Letters, 92, 44002 (2010)

  7. Mixing by cutting and shuffling
    G. Juarez, R. M. Lueptow, J. M. Ottino, R. Sturman and S. Wiggins
    Europhysics Letters, 91, 20003 (2010)

  8. Granular coarsening: Phase space and evolution analogies
    G. Juarez, R. M. Lueptow and J. M. Ottino
    Physical Review E, 81, 012301 (2010)

  9. Axial band scaling for bidisperse mixtures in granular tumblers
    G. Juarez, J. M. Ottino and R. M. Lueptow
    Physical Review E, 78, 031306 (2008)

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