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Publications

  1. Articles in scientific journals
  2. Books
  3. Theses

 

See also profiles on Publons, Orcid or Google Scholar.

 

 

1. Articles in scientific journals

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    Flexoelectric fluid membrane vesicles in spherical confinement

    Niloufar Abtahi, Lila Bouzar, Nadia Saidi-Amroun, Martin Michael Müller

    Abstract     Read more

    EPL, 131(1): 18001, 2020. See also arXiv:2006.04475.

     


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    Isometric bending requires local constraints on free edges

    Jemal Guven, Martin Michael Müller, Pablo Vázquez-Montejo

    While the shape equations describing the equilibrium of an unstretchable thin sheet that is free to bend are known, the boundary conditions that supplement these equations on free edges have remained elusive. Intuitively, unstretchability is captured by a constraint on the metric within the bulk. Naïvely one would then guess that this constraint is enough to ensure that the deformations determining the boundary conditions on these edges respect the isometry constraint. If matters were this simple, unfortunately, it would imply unbalanced torques (as well as forces) along the edge unless manifestly unphysical constraints are met by the boundary geometry. In this article, we identify the source of the problem: not only the local arc-length but also the geodesic curvature need to be constrained explicitly on all free edges. We derive the boundary conditions which follow. In contrast to conventional wisdom, there is no need to introduce boundary layers. This framework is applied to isolated conical defects, both with deficit as well, but more briefly, as surplus angles. Using these boundary conditions, we show that the lateral tension within a circular cone of fixed radius is equal but opposite to the radial compression, and independent of the deficit angle itself. We proceed to examine the effect of an oblique outer edge on this cone perturbatively demonstrating that both the correction to the geometry as well as the stress distribution in the cone kicks in at second order in the eccentricity of the edge.

     Reduce     Read more

    Math. Mech. Solids, 24: 4051, 2019. See also arXiv:1904.05855.

     


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    Helical Superstructure of Intermediate Filaments

    Lila Bouzar, Martin Michael Müller, René Messina, Bernd Nöding, Sarah Köster, Hervé Mohrbach, Igor M. Kulić

    Abstract     Read more

    Phys. Rev. Lett., 122: 098101, 2019. See also arXiv:1803.04691.

     


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    Vesicle dynamics in confined steady and harmonically modulated Poiseuille flows

    Zakaria Boujja, Chaouqi Misbah, Hamid Ez-Zahraouy, Abdelilah Benyoussef, Thomas John, Christian Wagner, Martin Michael Müller

    We present a numerical study of the time-dependent motion of a membrane vesicle in a channel under an imposed flow. In a Poiseuille flow the shape of the vesicle depends on the flow strength, the mechanical properties of the membrane, and the width of the channel. In a wide parameter region, the emerging snaking shape shows an oscillatory motion like a swimmer flagella even though the flow is stationary. We quantify this behavior by the amplitude and frequency of the oscillations of the vesicle's center of mass. The influence of an amplitude modulation of the imposed flow on the dynamics and shape of the snaking vesicle is also investigated. We find that this modulation---when sufficiently small---induces a modulation in amplitude and frequency of the center of mass of the snaking vesicle. For large modulation amplitudes transitions to static shapes are observed.

     Reduce     

    Phys. Rev. E, 98: 043111, 2018. See also arXiv:1810.04500.

     


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    Confining a fluid membrane vesicle of toroidal topology in an adhesive hard sphere

    Lila Bouzar, Ferhat Menas, Martin Michael Müller

    Abstract     Read more

    IOP Conf. Series: MSE, 186: 012021, 2017.

     


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    Squeezed helical elastica

    Lila Bouzar, Martin Michael Müller, Pierre Gosselin, Igor M. Kulić, Hervé Mohrbach

    Abstract     Read more

    Eur. Phys. J. E, 39: 114, 2016. See also arXiv:1606.03611.

     


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    How bio-filaments twist membranes

    Julien Fierling, Albert Johner, Igor M. Kulić, Hervé Mohrbach, Martin Michael Müller

    Abstract     

    Soft Matter, 12: 5747, 2016.

     


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    Toroidal membrane vesicles in spherical confinement

    Lila Bouzar, Ferhat Menas, Martin Michael Müller

    We investigate the morphology of a toroidal fluid membrane vesicle confined inside a spherical container. The equilibrium shapes are assembled in a geometrical phase diagram as a function of scaled area and reduced volume of the membrane. For small area the vesicle can adopt its free form. When increasing the area, the membrane cannot avoid contact and touches the confining sphere along a circular contact line, which extends to a zone of contact for higher area. The elastic energies of the equilibrium shapes are compared to those of their confined counterparts of spherical topology to predict under which conditions a topology change is favored energetically.

     Reduce     Read more

    Phys. Rev. E, 92: 032721, 2015. See also arXiv:1509.00765.

     


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    Non-linear buckling and symmetry breaking of a soft elastic sheet sliding on a cylindrical substrate

    Norbert Stoop, Martin Michael Müller

    Abstract     Read more

    Int. J. Non-Linear Mech., 75: 115, 2015. See also arXiv:1503.05030.

     


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    Crunching Biofilament Rings

    Julien Fierling, Martin Michael Müller, Hervé Mohrbach, Albert Johner, Igor M. Kulić

    Abstract     Read more

    Europhys. Lett., 107(6): 68002, 2014. See also arXiv:1408.6787.

     


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    Confotronic dynamics of tubular filaments

    Osman Kahraman, Hervé Mohrbach, Martin Michael Müller, Igor M. Kulić

    Abstract     Read more

    Soft Matter, 10(16): pp. 2836-2847, 2014. See also arXiv:1312.3106.

     


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    Whirling skirts and rotating cones

    Jemal Guven, J. A. Hanna, Martin Michael Müller

    Abstract     

    New J. Phys., 15: 113055, 2013. See also arXiv:1306.2619.

     


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    Myotubularin and PtdIns3P remodel the sarcoplasmic reticulum in muscle in vivo

    Leonela Amoasii, Karim Hnia, Gaëtan Chicanne, Andreas Brech, Belinda Simone Cowling, Martin Michael Müller, Yannick Schwab, Pascale Koebel, Arnaud Ferry, Bernard Payrastre, Jocelyn Laporte

    Abstract     

    J. Cell Sci., 126(8): 1806, 2013.

     


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    Dipoles in thin sheets

    Jemal Guven, J. A. Hanna, Osman Kahraman, Martin Michael Müller

    Abstract     Read more

    Eur. Phys. J. E, 36: 106, 2013. See also arXiv:1212.3262.

     


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    Fluid membrane vesicles in confinement

    Osman Kahraman, Norbert Stoop, Martin Michael Müller

    Abstract     Read more

    New J. Phys., 14: 095021, 2012.

     


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    Petal shapes of sympetaleous flowers: the interplay between growth, geometry and elasticity

    Martine Ben Amar, Martin Michael Müller, Miguel Trejo

    Abstract     Read more

    New J. Phys., 14: 085014, 2012. Also featured in the Highlights of 2012.

     


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    Morphogenesis of membrane invaginations in spherical confinement

    Osman Kahraman, Norbert Stoop, Martin Michael Müller

    Abstract     Read more

    Europhys. Lett., 97(6): 68008, 2012. See also arXiv:1201.2518.

     


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    Conical instabilities on paper

    Jemal Guven, Martin Michael Müller, Pablo Vázquez-Montejo

    The stability of the fundamental defects of an unstretchable flat sheet is examined. This involves expanding the bending energy to second order in deformations about the defect. The modes of deformation occur as eigenstates of a fourth-order linear differential operator. Unstretchability places a global linear constraint on these modes. Conical defects with a surplus angle exhibit an infinite number of states. If this angle is below a critical value, these states possess an n-fold symmetry labeled by an integer, n ≥ 2. A nonlinear stability analysis shows that the 2-fold ground state is stable, whereas excited states possess 2(n - 2) unstable modes which come in even and odd pairs.

     Reduce     Read more

    J. Phys. A: Math. Theor., 45(1): 015203, 2012. See also arXiv:1107.5008.

     


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    Interface-mediated interactions: Entropic forces of curved membranes

    Pierre Gosselin, Hervé Mohrbach, Martin Michael Müller

    Abstract     Read more

    Phys. Rev. E, 83(5): 051921, 2011. See also arXiv:1011.1221.

     


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    Self-Contact and Instabilities in the Anisotropic Growth of Elastic Membranes

    Norbert Stoop, Falk K. Wittel, Martine Ben Amar, Martin Michael Müller, Hans J. Herrmann

    We investigate the morphology of thin discs and rings growing in circumferential direction. Recent analytical results suggest that this growth produces symmetric excess cones (e-cones). We study the stability of such solutions considering self-contact and bending stress. We show that, contrary to what was assumed in previous analytical solutions, beyond a critical growth factor, no symmetric e-cone solution is energetically minimal any more. Instead, we obtain skewed e-cone solutions having lower energy, characterized by a skewness angle and repetitive spiral winding with increasing growth. These results are generalized to discs with varying thickness and rings with holes of different radii.

     Reduce     Read more

    Phys. Rev. Lett., 105(6): 068101, 2010. See also arXiv:1007.1871.

     


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    Cell Model Approach to Membrane Mediated Protein Interactions

    Martin Michael Müller, Markus Deserno

    Abstract     Read more

    Prog. Theor. Phys. Suppl., 184: pp. 351-363, 2010.

     


  •  

    Hamiltonian formulation of surfaces with constant Gaussian curvature

    Miguel Trejo, Martine Ben Amar, Martin Michael Müller

    Abstract     Read more

    J. Phys. A: Math. Theor., 42(42): 425204, 2009.

     


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    Local Membrane Mechanics of Pore-Spanning Bilayers

    Ingo Mey, Milena Stephan, Eva K. Schmitt, Martin Michael Müller, Martine Ben Amar, Claudia Steinem, Andreas Janshoff

    Abstract     Read more

    J. Am. Chem. Soc., 131(20): pp. 7031-7039, 2009.

     


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    Elasticity Mapping of Pore-Suspending Native Cell Membranes

    Bärbel Lorenz, Ingo Mey, Siegfried Steltenkamp, Tamir Fine, Christina Rommel, Martin Michael Müller, Alexander Maiwald, Joachim Wegener, Claudia Steinem, Andreas Janshoff

    Abstract     Read more

    Small, 5(7): pp. 832-838, 2009.

     


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    Conical Defects in Growing Sheets

    Martin Michael Müller, Martine Ben Amar, Jemal Guven

    Abstract     Read more

    Phys. Rev. Lett., 101(15): 156104, 2008. See also arXiv:0807.1814.

     


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    How paper folds: bending with local constraints

    Jemal Guven, Martin Michael Müller

    Abstract     Read more

    J. Phys. A: Math. Theor., 41(5): 055203, 2008. See also arXiv:0712.0978.

     


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    Contact lines for fluid surface adhesion

    Markus Deserno, Martin Michael Müller, Jemal Guven

    Abstract     Read more

    Phys. Rev. E, 76(1): 011605, 2007. See also cond-mat/0703019.
    Also featured in the Virtual Journal of Biological Physics Research.

     


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    Balancing torques in membrane-mediated interactions: Exact results and numerical illustrations

    Martin Michael Müller, Markus Deserno, Jemal Guven

    Abstract     Read more

    Phys. Rev. E, 76(1): 011921, 2007. See also cond-mat/0702340.
    Also featured in the Virtual Journal of Biological Physics Research.

     


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    Aggregation and vesiculation of membrane proteins by curvature-mediated interactions

    Benedict J. Reynwar, Gregoria Illya, Vagelis A. Harmandaris, Martin Michael Müller, Kurt Kremer, Markus Deserno

    Abstract     Read more

    Nature 447(7143): pp. 461-464, 2007.

     


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    How to determine local elastic properties of lipid bilayer membranes from atomic-force-microscope measurements: A theoretical analysis

    Davood Norouzi, Martin Michael Müller, Markus Deserno

    Measurements with an atomic force microscope (AFM) offer a direct way to probe elastic properties of lipid bilayer membranes locally: provided the underlying stress-strain relation is known, material parameters such as surface tension or bending rigidity may be deduced. In a recent experiment a pore-spanning membrane was poked with an AFM tip, yielding a linear behavior of the force-indentation curves. A theoretical model for this case is presented here which describes these curves in the framework of Helfrich theory. The linear behavior of the measurements is reproduced if one neglects the influence of adhesion between tip and membrane. Including it via an adhesion balance changes the situation significantly: force-distance curves cease to be linear, hysteresis and nonzero detachment forces can show up. The characteristics of this rich scenario are discussed in detail in this article.

     Reduce     Read more

    Phys. Rev. E, 74(6): 061914, 2006. See also cond-mat/0602662.
    Also featured in the Virtual Journal of Biological Physics Research.

     


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    Mechanical Properties of Pore-Spanning Lipid Bilayers Probed by Atomic Force Microscopy

    Siegfried Steltenkamp, Martin Michael Müller, Markus Deserno, Christian Hennesthal, Claudia Steinem, Andreas Janshoff

    Abstract     Read more

    Biophys. J., 91(1): pp. 217-226, 2006.

     


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    Interface mediated interactions between particles -- a geometrical approach

    Martin Michael Müller, Markus Deserno, Jemal Guven

    Abstract     Read more

    Phys. Rev. E, 72(6): 061407, 2005. See also cond-mat/0506019.
    Also featured in the Virtual Journal of Biological Physics Research.

     


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    Geometry of surface-mediated interactions

    Martin Michael Müller, Markus Deserno, Jemal Guven

    Abstract     Read more

    Europhys. Lett., 69(3): pp. 482-488, 2005. See also cond-mat/0409043.

     


 

 

2. Books

 

  • New Trends in the Physics and Mechanics of Biological Systems
    Lecture Notes of the Les Houches Summer School, vol. 92 (Oxford University Press, 2011),
    edited by Martine Ben Amar, Alain Goriely, Martin Michael Müller and Leticia Cugliandolo.

    Chapter 9:
    The physics of the cell membrane
    Martin Michael Müller and Martine Ben Amar.

 

 


 

 

3. Theses

  • Theoretical examinations of interface mediated interactions between colloidal particles, diploma thesis (2004).


  • Theoretical studies of fluid membrane mechanics, dissertation (2007).


  • Symmetry breaking in bioelasticity, habilitation thesis (2015).

 

 

 
     

 

     © Martin Michael Müller