Department of Applied Physics

Active Matter

Current focus

  • Active matter: We investigate behavior of biological micro/milliswimmers in complex environments and interfaces. We also develop, engineer and synthesize artificial systems that mimic naturally occurring active materials.
  • Non-equilibrium systems: Active matter is just one example of non-equilibrium systems. We are interested in the transition between equilibrium and non-equilibrium self-assembly.
  • Fluids and colloids in EM fields: We are interested in the ways that fluids and colloidal matter interact with electric and magnetic fields. We also develop new electromagnetic microtweezing tools for soft matter research.

Open positions

We always welcome applications from enthusiastic researchers of all levels (from students to post-docs). Contact Prof. Jaakko Timonen for details.

Research highlights

  • Daniel D., Timonen J.V.I., Li R., Velling S.J., Aizenberg J.A.,
    Oleoplaning droplets on lubricated surfaces,
    Nature Physics (2017). (link)

  • Timonen J.V.I., Raimondo C., Pilans D., Pillai P.P., Grzybowski B.A.,
    Trapping, Manipulation, and Crystallization of Live Cells Using Magnetofluidic Tweezers,
    Nanoscale Horizons 2, 50-54 (2017). (link)

  • Timonen J.V.I., Demirörs A.F., and Grzybowski B.A., 
    Magnetofluidic Tweezing of Nonmagnetic colloids,
    Advanced Materials 28, 3453-3459 (2016). (link)

  • Timonen J.V.I., Latikka M., Leibler L., Ras R.H.A., and Ikkala O., 
    Switchable Static and Dynamic Self-Assembly of Magnetic Droplets on Superhydrophobic Surfaces,
    Science 341, 253-257 (2013). (link) (press release)

  • Timonen J.V.I., Latikka M., Ikkala O., Ras R.H.A., 
    Free-Decay and Resonant Methods for Investigating the Fundamental Limit of Superhydrophobicity,
    Nature Communications 4, 2398 (2013). (link) (press release)

  • Timonen J.V.I., Seppälä E.T., Ikkala O., and Ras R.H.A., 
    From hot-injection synthesis to heating-up synthesis of cobalt nanoparticles: observation of kinetically controllable nucleation,
    Angewandte Chemie International Edition 50, 2080-2084 (2011). (link)


  • Wet chemistry lab equipped for nanoparticle/colloid synthesis
  • Bioroom equipped for BSL1 micro-organisms
  • Physical measurements lab equipped with
    -  Nikon Ti-E and Zeiss Z1 inverted microscopes
    -  Andor iXon Ultra 888 EMCCD and Zyla 4.2 sCMOS cameras
    -  Photron APX-RS high-speed camera (color, 1024x1024 @ 3000 fps)
    -  Keysight/Keithley precision measurement units and power supplies
  • Other facilities at our disposal
    Nanomicroscopy center (electron microscopy, x-ray scattering) 
    Micronova (nano/microfabrication)
    -  Department of Applied Physics (general tools and equipment)

Latest publications

Ferrofluid Microdroplet Splitting for Population-Based Microfluidics and Interfacial Tensiometry

Mika Latikka, Matilda Backholm, Avijit Baidya, Alberto Ballesio, Amandine Serve, Grégory Beaune, Jaakko V.I. Timonen, Thalappil Pradeep, Robin H.A. Ras 2020 Advanced Science

Controllable coacervation of recombinantly produced spider silk protein using kosmotropic salts

Pezhman Mohammadi, Jonkergouw Christopher, Grégory Beaune, Peter Engelhardt, Ayaka Kamada, Jaakko V.I. Timonen, Tuomas P.J. Knowles, Merja Penttila, Markus B. Linder 2020 Journal of Colloid and Interface Science

Magnetic Field-Driven Deformation, Attraction, and Coalescence of Nonmagnetic Aqueous Droplets in an Oil-Based Ferrofluid

C. Rigoni, J. Fresnais, D. Talbot, R. Massart, R. Perzynski, J. C. Bacri, A. Abou-Hassan 2020 Langmuir

Magnetic microdroplets as a method to extract antibodies from their growth media

Hedar Al-Terke, Mika Latikka, Jaakko Timonen, Arja Paananen, Jussi J. Joensuu, Robin Ras 2019 Abstracts of papers of the American Chemical Society

Phthalocyanine–Virus Nanofibers as Heterogeneous Catalysts for Continuous-Flow Photo-Oxidation Processes

Eduardo Anaya-Plaza, Ana Aljarilla, Grégory Beaune, Jaakko V.I. Timonen, Andrés de la Escosura, Tomás Torres, Mauri A. Kostiainen 2019 Advanced Materials

Highly Luminescent Gold Nanocluster Frameworks

Sourov Chandra, Nonappa Nonappa, Grégory Beaune, Anirban Som, Shaochen Zhou, Jouko Lahtinen, Hua Jiang, Jaakko Timonen, Olli Ikkala, Robin Ras 2019 ADVANCED OPTICAL MATERIALS

Supramolecular Self-Assembly of Nanoconfined Ionic Liquids for Fast Anisotropic Ion Transport

Tomy Cherian, Danilo Rosa Nunes, Thomas G. Dane, Johan Jacquemin, Ulla Vainio, Teemu T. T. Myllymaki, Jaakko V. Timonen, Nikolay Houbenov, Manuel Marechal, Patrice Rannou, Olli Ikkala 2019 Advanced Functional Materials

Clustering and anisotropic correlated percolation in polar flocks

Nikos Kyriakopoulos, Hugues Chate, Francesco Ginelli 2019 Physical Review E

Origins of Extreme Liquid Repellency on Structured, Flat, and Lubricated Hydrophobic Surfaces

Dan Daniel, Jaakko V.I. Timonen, Ruoping Li, Seneca J. Velling, Michael J. Kreder, Adam Tetreault, Joanna Aizenberg 2018 Physical Review Letters

Structural origins of coloration in the spider Phoroncidia rubroargentea Berland, 1913 (Araneae: Theridiidae) from Madagascar

Sarah Kariko, Jaakko V.I. Timonen, James C. Weaver, Dvir Gur, Carolyn Marks, Leslie Leiserowitz, Mathias Kolle, Ling Li 2018 Journal of the Royal Society Interface
More information on our research in the Research database.
Research database

Earlier publications (2010 - 2017)

Scientific publications by the Active Matter group pre-2018.

  • Published:
  • Updated:
URL copied!