TOP > Members > A03 project

A03. Dynamics of Non-Equilibrium Structures

Soft matter driven far from equilibrium manifest striking properties as a result of their high sensitivity to external fields. In those circumstances non-equilibrium fluctuations and structural transitions at a microscopic level strongly affect macroscopic spatio-temporal structures of soft matter. A03 team studies non-equilibrium phenomena in liquid crystals, polymers, and biological materials with new experimental and theoretical tools from the view point of statistical mechanics.

Research Projects

Sano group
Non-Equilibrium Dynamics and Structural Transitions in Soft Small Systems
 
[ Leader ] [ Member ] [ Collaborator ]
Masaki Sano
University of Tokyo
 
 
Yoshihiro Murayama
Tokyo University of Agriculture and Technology
Takahiro Harada
University of Tokyo
 
 
Tabe group
Spatio-Temporal Transformation of Molecular Motion to Macroscopic Dynamics in Two-Dimensional Liquid Crystals
 
[ Leader ] [ Member ]
Yuka Tabe
Waseda University
 
 
 
Makoto Yoneya
National Institute of Advanced Industrial Science and Technology
Toda group
Non-Equilibrium Structural Evolution in Crystallization from Viscoelastic Soft Matter
 
[ Leader ] [ Member ] [ Member ] [ Member ]
Akihiko Toda
Hiroshima University
Shinpei Tanaka
Hiroshima University
Yoshihiro Yamazaki
Waseda University
Ken Taguchi
Hiroshima University
research subject
Understanding crystallization mechanism is essential in the structural control of softmaterials of high performance. Owing to the self-organized viscoelastic field, softmaterials crystallize under conditions far from equilibrium, which leads to the evolution of various spatio-temporal patterns such as self-excited oscillation, morphological instability, and complex networks. We approach the crystallization of softmaterials with recent theoretical developments in the field of non-equilibrium and non-linear dynamics. We are interested in the phenomena of self-excited oscillations in crystal orientation and growth rate, instability of crystal-melt interface, and network patterns caused by the competition between different phase transitions. They are observed in a wide range of materials from crystalline polymers, organic molecules, to biological macromolecules such as proteins. All those phenomena are strongly influenced by the viscoelastic field. For the understanding of these crystallization process and its spatio-temporal control, we set up experimental systems to observe and control the materials in the spatial resolution of nm and in the temporal resolution of micro seconds. Mathematical modeling based on computer simulation is also used to complement the experiments.
Ohta group
Dynamical Coupling between Structures and Transports in Soft Matter
 
[ Leader ] [ Member ] [ Collaborator ]
Takao Ohta
Kyoto University
Jun Yamamoto
Kyoto University
Yoichi Takanishi
Kyoto University
research subject
The aim of our research is to clarify, both theoretically and experimentally, the dynamical coupling between structures and transports, which is one of the characteristic features in the hierarchical order in soft matter. The nonlinear response theory will be developed including the topological change of the structures and the kinetics of structural transitions will also be investigated by numerical simulations. Experimentally we will use the method of external field to excite and choose the specific degrees of freedom among the individual dynamical modes. Imposing a space-time dependent field, we manipulate some selected modes and detect their response by utilizing another spatio-temporal probe to get information of the dynamical coupling between the structures and the transports. Our goal is to understand formation of the non-equilibrium structures and the stability in a unified way by a cooperative research of theory and experiments.
To Top

Public Participation Research (2009-2010)

Sasa group
Jamming Transition from Non-equilibrium Statistical Mechanics
 
[ Leader ]
Shin-ichi Sasa
University of Tokyo
research subject
It is observed that the collective motion of a system ceases as the result of mutual interruption among elements. We call such phenomena jamming transitions (in a sense wider than usual.) Granular systems under shear provides a typical example; The transition to no flow state corresponds to a jamming transition. Since such a singular transportation phenomenon occurs out of linear response regime, this provides us a good target for (not-established) non-equilibrium statistical mechanics. On the basis of recent developments, in this project, I synthesize the two research subjects, jamming transitions and fundamentals of non-equilibrium statistical mechanics.
Tomishige group
Single Molecule Study of the Coupled System of Transporting Motor Proteins
 
[ Leader ]
Michio Tomishige
University of Tokyo
research subject
Molecular motor proteins are the soft material that actively changes its conformations by converting chemical energy to mechanical work. In our project, we will establish a in vitro system in which multiple molecular motors are assembled and transport a cargo as a team. Then we observe the collective behavior of the system and the conformational states of individual motors simultaneously. These experimental approaches could help us to understand how the strain transmitted among each molecular motors coordinate the behavior of each molecules.
Takiguchi group
Real-time Imaging and Theoretical Analysis of Dynamic Interactions between Cytoskeletal Proteins and Lipid Bilayers
 
[ Leader ] [ Member ] [ Member ]
Kingo Takiguchi
Nagoya University
Makoto Kinoshita
Nagoya University
Tamiki Umeda
Kobe University
research subject
Cell shape is determined by the interplay between the lipid bilayer and the underlying network of protein polymers. To explore unknown determinants involved in cell morphogenesis, we observed dynamic transformation of unlabelled large liposomes that are comparable in dimension with eukaryotic cells by optical dark-field microscopy. Septins are ubiquitous nucleotide-binding cytoskeleton conserved from yeast to man. Many studies have consistently indicated the requirement of septins for diverse morphogenetic events in vivo. However, previous studies have little addressed the biophysical basis of the septin-mediated membrane morphogenesis. We have tried to monitor the behaviors of giant liposomes in the presence of septin, and successfully revealed that septin induces robust and rapid tubulation of giant liposomes, and that ultrastructural analysis revealing uniform trussing of the liposome membrane by circumferential arrays of septin filaments. It indicates that the novel unique mode of lipid-protein polymer interaction.
Hayakawa group
Study of Unified Description of Jamming Transition and Glass Transition
 
[ Leader ]
Hisao Hayakawa
Kyoto University
research subject
The main purpose of my study is to understand both the jamming transition and the glass transition which are observed in dense soft matter based on an unified view. We have already succeeded to extend the mode-coupling theory in terms of the glass transition from the field theory, to formulate the liquid theory beyond the conventional mode-coupling theory for sheared dense ststems, and to predict the critical exponents for the jamming transition as welll as the divergences of the first peak of the radial distribution function and the viscosity. In this project, I will promote the above mentioned researches and clarify an unified view for the dense soft matter in the vicinity of the jamming and the glass transitions.
Miyata group
Phase Separation Process in Polymer Mixtures under Stationary Non-Equilibrium Conditions Generated by Computer-Assisted Irradiation Method
 
[ Leader ] [ Member ]
Qui Tran-Cong-Miyata
Kyoto Institute of Technology
Tomohisa Norisue
 
Kyoto Institute of Technology
research subject
In this research project, phase separation process of multi-component polymer mixtures induced by computer-assisted irradiation (CAI) method will be experimentally investigated. The newly constructed optical microscope system equipped with a digital projector will be used to observe in situ the resulting morphology induced by UV irradiation. The kinetics of phase separation under these stationary non-equilibrium conditions will be analyzed to gain information on phase separation process of polymer systems far from thermodynamic equilibrium. Finally, the ordered structures resulting from these phase separation processes will be used to design various conducting polymers via the combination the co-continuous structures with carbon nanotubes.
Kageshima group
Nonequilibrium Dynamics of Single Polymer Chain Studied through Viscoelasticity Measurement
 
[ Leader ]
Masami Kageshima
Tokyo Gakugei University
research subject
The goal of the present research is to develop an experimental method to analyze viscoelastic response of polymer in single-molecule scale, and to discuss the viscoelasticity from a viewpoint of molecular scale structure. Frequency-dependent viscoelasticity of a single polymer chain is measured with a home-built atomic force microscopy (AFM) by exciting the force sensor with an oscillatory force up to 1 MHz. Phase transition is induced in the polymer chain by applying a tensile external force to it, and its relation to the viscoelasticity data is being discussed.
Mizuno group
Nonequilibrium Mechanics of Biological Soft Matter
 
[ Leader ]
Daisuke Mizuno
Kyushu University
research subject
Life is composed of soft materials which are driven far from equilibrium by the active agents such as molecular motors. Utilizing various non-equilibrium and nonlinear effects typically observed in these biological soft materials, cells adapt/control their physical properties quickly and economically without necessity to change their chemical constituents or structures. In this contribution, we develop an experimental technique to measure the mechanics of soft materials driven out of equilibrium by molecular motors and/or applied external fields. Our goal is to give experimental information to establish the statistical mechanics governing the non-equilibrium processes in life.
Matsuyama group
Phase Ordering and Dynamics of Rodlike Colloids Dispersed in Liquid Crystalline Solvents
 
[ Leader ]
Akihiko Matsuyama
Kyusyu Institute of Technology
research subject
Rodlike colloidal particles such as carbon nanotubes have received great attention because of their unique structures and properties as well as possible applications such as nano-sensors and devices. For realizing these applications, one important concept is to align rodlike particles. An alternative approach is to align rodlike colloidal particles with the aid of nematic solvents. In this project, we theoretically study phase separations and dynamics in mixtures of a liquid crystal and a rodlike colloidal particle. We focus on (1) the phase behavior of the liquid crystal-rodlike colloid mixtures, (2) the phase ordering induced by external fields such as electric and magnetic fields, and (3) the phase ordering dynamics due to two orientational order parameters.
Fukao group
Glassy Dynamics in Glass-forming Materials
 
[ Leader ] [ Member ]
Koji Fukao
Ritsumeikan University
Kenji Nakamura
Ritsumeikan University
research subject
If a liquid is cooled down from high temperature to a temperature below melting temperature, a supercooled liquid state is obtained. The glassy state can be rearched through this supercooled liquid state under an appropriate cooling condition. This is called glass transition and the glassy state has a non-equilibrium nature. In the glassy state, aging phenomena are observed where the non-equilibrium glassy state approaches an equilibrium state and a non-equilibrium relaxation is accompanied. During aging process in the glassy states some interesting phenomena such as memory effect and rejuvenation effect are observed with measurements of ac-susceptibility. In this study, dielectric relaxation spectroscopy and temperature modulated differential scanning calorimetry are used in order to elucidate the nature of non-equilibrium relaxation phenomena during the aging process for glassy states of polymers, which is most important representative of soft matters.
Tero group
Non-linear Phase Separation of Lipid Bilayers Induced by External Fields
 
[ Leader ]
Ryugo Tero
Toyohashi University of Technology
research subject
Lipid bilayer membrane is the fundamental architecture of cell membranes, and its phase separation plays one of key roles in the condensation and dispersion of molecules during biological membrane reaction. The target of this project is the dynamic behavior of non-equilibrium bilayer phase separations. I have found that the surface force field on oxides and photo-irradiation induce mesoscopic phase separation in lipid bilayer membranes mainly consisting of sphingolipids and cholesterol. The structures and physical properties of those external-filed induced phase separation are investigated in-situ by fluorescence microscopy and atomic force microscope.
To Top