Research Topics

Non-Equilibrium Systems, Jamming, Glassy Dynamics, and Gels:

  • Exploring the energy landscape of non-equilibrium transitions
  • We study non-equilibrium transitions like thermal jamming or the clustering transition by exploring the energy landscape of passive or active soft particulate systems.
  • M. Gimperlein and M. Schmiedeberg in cooperation with M. Maiti (Münster)
  • Selected Publications:
    M. Maiti and M. Schmiedeberg, Scientific Reports 8, 1837 (2018);
    L. Milz and M. Schmiedeberg, Phys. Rev. E 88, 062308 (2013);
    M. Maiti et al., J. of Phys.: Cond. Matter 31, 165101 (2019);
    M. Maiti et al., Eur. Phys. J. E 42, 38 (2019)
  • Supported by a grant of the DFG (Schm 2657/3).
  • Gel formation
  • The slowdown of dynamics during gelation in colloid-polymer mixtures is attended by the formation of directed chains of colloids. This structural transition corresponds to a directed percolation transition.
  • M. Gimperlein and M. Schmiedeberg in cooperation with the group of S.U. Egelhaaf (Düsseldorf)
  • Selected Publications:
    M. Kohl, R.F. Capellmann, M. Laurati, S.U. Egelhaaf, and M. Schmiedeberg, Nature Comm. 7, 11817 (2016);
    M. Kohl and M. Schmiedeberg, EPJ E 40, 71 (2017)
  • Glassy dynamics of soft, hard, or active sphere systems
  • While for small overlaps the dynamics of soft repulsive spheres can be mapped onto the hard sphere behavior, large overlaps lead to multiple glass transitions and attractions to even more complex behavior.
  • M. Schmiedeberg in cooperation with the group of A.J. Liu (Philadelphia)
  • Selected Publications:
    M. Schmiedeberg, Phys. Rev. E 87, 052310 (2013);
    M. Schmiedeberg et al., EPL 96, 36010 (2011);
    T.K. Haxton et al., Phys. Rev. E 83, 031503 (2011);
    M. Maiti et al., J. of Phys.: Cond. Matter 31, 165101 (2019)
  • Structure and glassy dynamics close to a wall
  • Due to the broken anisotropy, studies of a hard sphere system close to a wall reveal interesting insights to cage breaking and glassy dynamics.
  • M. Schmiedeberg in cooperation with A. Härtel (Freiburg) and R.A. Solórzano Kraemer (Mexico City)
  • Selected Publications:
    A. Härtel et al., Phys. Rev. E 92, 042310 (2015);
    M. Kohl et al., J. of Phys.: Cond. Mat. 28, 505001 (2016)
  • Supported within the Emmy-Noether-Program of the DFG (Schm 2657/2).

Complex Colloidal Structures:

  • Phases in colloid-polymer mixtures
  • We determine the complex phase behavior of charged colloidal particles that are surrounded by polymers. The resulting depletion attractions lead to a competition of different characteristic interaction length scales.
  • A. Mijailović and M. Schmiedeberg in cooperation with E.C. Oğuz (Tel Aviv)
  • Selected Publication:
    E.C. Oğuz et al., Phys. Rev. E 98, 052601 (2018)
  • Complex structures obtained with patchy colloids
  • We are interested how preferred binding angles in the case of patchy colloids influence the resulting self-assembled structures. A phase field crystal model is developed for a theoretical description.
  • R. Weigel and M. Schmiedeberg
  • Selected Publication:
    A. Gemeinhardt et al., EPJ E 41, 126 (2018);
    A. Gemeinhardt et al., EPL 126, 38001 (2019)
  • Supported by a grant of the DFG (Schm 2657/4).
  • Colloidal particles on incommensurate surfaces
  • Ordering, growth, and complex structures on incommensurate substrates.
  • M. Schmiedeberg in cooperation with the group of H. Löwen (Düsseldorf)
  • Selected Publications:
    T. Neuhaus et al., EPJ ST 223, 373 (2014);
    T. Neuhaus et al., PRL 110, 118301 (2013)
  • Supported within the Emmy-Noether-Program (Schm 2657/2) and the Priority Program SPP 1296 of the DFG.

Soft Quasicrystals:

  • Growth and melting of soft quasicrystals
  • We investigate properties of intrinsic colloidal quasicrystals using a phase field crystal model or simulations.
  • M. Martinsons, S. Wolf, R. Weigel, and M. Schmiedeberg in cooperation with M. Engel (technical faculty, Erlangen), C.V. Achim (Conception), H. Löwen (Düsseldorf), and E.C. Oğuz (Tel Aviv)
  • Selected Publications:
    C.V. Achim et al., PRL 112, 255501 (2014);
    M. Schmiedeberg et al., Phy. Rev. E 96, 012602 (2017);
    M. Martinsons et al., J. of Phys.: Cond. Mat. 30, 255403 (2018);
    A. Gemeinhardt et al., EPJ E 41, 126 (2018)
  • Additional degrees of freedom in quasicrystals: Phasons
  • Phonons are well-known modes in periodic crystals. In quasicrystals, which are aperiodic, additional degrees of freedom (correlated rearrangements termed phasons) occur and change their properties.
  • M. Martinsons and M. Schmiedeberg in cooperation with S.C. Kapfer (FAU), J. Roth (Stuttgart), and H. Stark (TU Berlin)
  • Selected Publications:
    J.A. Kromer et al., PRL 108, 218301 (2012);
    J. Hielscher et al., J. of Phys.: Cond. Mat. 29, 094002 (2017)
  • Supported within the Emmy-Noether-Program of the DFG (Schm 2657/2).
  • Quasicrystals composed of particles with preferred binding angles
  • We want to understand how quasicrystals can be stabilized for particles that support only one one length scale but in addition have a preference for some binding angles (e.g., patchy colloids).
  • R. Weigel and M. Schmiedeberg
  • Selected Publication:
    A. Gemeinhardt et al., EPL 126, 38001 (2019);
    A. Gemeinhardt et al., EPJ E 41, 126 (2018)
  • Supported by a grant of the DFG (Schm 2657/4).
  • Light-induced colloidal quasicrystals
  • By employing the interference patterns of laser beams, a large varity of colloidal quasicrystals can be obtained and studied.
  • M. Schmiedeberg in cooperation with the groups of C. Bechinger (Konstanz), H. Stark (TU Berlin), and J. Roth (Stuttgart)
  • Selected Publications:
    F. Rühle et al., EPJ E 38, 54 (2015);
    M. Schmiedeberg et al., EPJ E 32, 25 (2010);
    J. Mikhael et al., PNAS 107, 7214 (2010)
  • Supported within the Emmy-Noether-Program of the DFG (Schm 2657/2).
  • Photonic and quantum quasicrystals, aperiodic Lorentz gases
  • We are interested in the photonic as well as quantum properties of quasicrystals. Furthermore, we explore the different types of trajectories in quasicrystalline Lorentz gases.
  • M. Schmiedeberg in cooperation with the group of K.P. Schmidt (FAU), R.A. Solórzano Kraemer and D.P. Sanders (Mexico City)
  • Selected Publication:
    Kraemer et al., Phys. Rev. E 92, 052131 (2015)

Normal and Anomalous Diffusion:

  • Browian particle on a rough surface
  • Intermediate and asymptotic regimes of motion of a colloidal particle in a one-dimensional random laser potential.
  • M. Schmiedeberg in cooperation with the group of S.U. Egelhaaf (Düsseldorf)
  • Selected Publications:
    R.D.L. Hanes et al., Phys. Rev. E 88, 062133 (2013);
    R.D.L. Hanes et al., Soft Matter, 8, 2714 (2012)
  • Continuous-Time Random Walks
  • We study and compare different Lévy-Walk and Lévy-Flight models.
  • M. Schmiedeberg in cooperation with the group of V.Yu. Zaburdaev
  • Selected Publications:
    D. Froemberg et al., Phys. Rev. E 91, 022131 (2015);
    M. Schmiedeberg et al., J. Stat. Mech. P12020 (2009);
    V.Yu. Zaburdaev et al., Phys. Rev. E 78, 011119 (2008)

Biophysics:

  • Phase field crystal models for biological systems
  • We are interested in pattern formation processes in systems consisting of living "particles". We develop and study phase field crystal models for their description.
  • D. Arold and M. Schmiedeberg
  • Motility and Crowding of bacteria
  • Twitching motility of Neisseria gonorrhoeae.
  • L. Self and M. Schmiedeberg in cooperation with V.Yu. Zaburdaev (biology department, Erlangen) and other coworkers
  • Publication:
    V.Yu. Zaburdaev et al., Biophysical Journal 107, 1523 (2014)
  • Visco-elastic systems
  • We explore the microrheological properties of visco-elastic matter.                                                                                                         
  • M. Schmiedeberg
  • Publication:
    M. Schmiedeberg et al., EPL 69, 629 (2005)

Didactics and Physics Competitions:

  • New type of seminar and Physicists' Tournaments
  • I started a new type of seminar that deals with the problems of the International Physicists' Tournament where the students do their research on the problems of this tournament. Furthermore, I am involved as juror in the German Young Physicists' Tournament and in drafting problems for the DOPPLERS competition.
  • M. Schmiedeberg in cooperation with A. Fösel (didactics, Erlangen)
  • see also: FAUltiere für die Physik

Complete list of publications of M. Schmiedeberg: .