This page has only limited features, please log in for full access.

Unclaimed
Hiroshi Koibuchi
National Institute of Technology (KOSEN), Sendai College, 8 Nodayama, Medeshima-Shiote, Natori-shi, Miyagi 981-1239, Japan

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Article
Published: 01 July 2021 in Physical Review B
Reads 0
Downloads 0

Skyrmions in chiral magnetic materials are topologically stable and energetically balanced spin configurations appearing under the presence of ferromagnetic interaction (FMI) and Dzyaloshinskii-Moriya interaction (DMI). Much of the current interest has focused on the effects of magnetoelastic coupling on these interactions under mechanical stimuli, such as uniaxial stresses for future applications in spintronics devices. Recent studies suggest that skyrmion shape deformations in thin films are attributed to an anisotropy in the coefficient of DMI, such that Dx≠Dy, which makes the ratio λ/D anistropic, where the coefficient of FMI λ is isotropic. It is also possible that λx≠λy while D is isotropic for λ/D to be anisotropic. In this paper, we study this problem using a modeling technique constructed based on Finsler geometry (FG). Two possible FG models are examined: In the first (second) model, the FG modeling prescription is applied to the FMI (DMI) Hamiltonian. We find that these two different FG models' results are consistent with the reported experimental data for skyrmion deformation. We also study responses of helical spin orders under lattice deformations corresponding to uniaxial extension/compression and find a clear difference between these two models in the stripe phase, elucidating which interaction of FMI and DMI is deformed to be anisotropic by uniaxial stresses.

ACS Style

Sahbi El Hog; Fumitake Kato; Hiroshi Koibuchi; Hung T. Diep. Finsler geometry modeling and Monte Carlo study of skyrmion shape deformation by uniaxial stress. Physical Review B 2021, 104, 024402 .

AMA Style

Sahbi El Hog, Fumitake Kato, Hiroshi Koibuchi, Hung T. Diep. Finsler geometry modeling and Monte Carlo study of skyrmion shape deformation by uniaxial stress. Physical Review B. 2021; 104 (2):024402.

Chicago/Turabian Style

Sahbi El Hog; Fumitake Kato; Hiroshi Koibuchi; Hung T. Diep. 2021. "Finsler geometry modeling and Monte Carlo study of skyrmion shape deformation by uniaxial stress." Physical Review B 104, no. 2: 024402.

Conference paper
Published: 01 January 2021 in Journal of Physics: Conference Series
Reads 0
Downloads 0

Turing patterns are known to be described by diffusion reaction (DR) equations, and the patterns become zebra-like anisotropic if the diffusion constant is directionally dependent. However, the origin of this dependence is unclear. In this study, we report that Turing patterns can be studied with the Finsler geometry (FG) modeling technique by applying a hybrid numerical technique, which combines DR equations and the Monte Carlo (MC) technique. In the DR equations and the Hamiltonian for MC, the Finsler metric is introduced using internal degrees of freedom. We numerically show that anisotropic patterns appear according to a constraint given by some external forces applied to the internal degrees of freedom. In this FG modeling technique, direction-dependent diffusion constants are unnecessary, and these constants automatically or effectively become anisotropic. We consider that the internal degrees of freedom introduced for the Finsler metric play an essential role in the anisotropic patterns.

ACS Style

Hiroshi Koibuchi; Masahiko Okumura; Shuta Noro. Finsler geometry modeling for anisotropic diffusion in Turing patterns. Journal of Physics: Conference Series 2021, 1730, 012035 .

AMA Style

Hiroshi Koibuchi, Masahiko Okumura, Shuta Noro. Finsler geometry modeling for anisotropic diffusion in Turing patterns. Journal of Physics: Conference Series. 2021; 1730 (1):012035.

Chicago/Turabian Style

Hiroshi Koibuchi; Masahiko Okumura; Shuta Noro. 2021. "Finsler geometry modeling for anisotropic diffusion in Turing patterns." Journal of Physics: Conference Series 1730, no. 1: 012035.

Journal article
Published: 01 December 2020 in Physics of Fluids
Reads 0
Downloads 0

Protoplasmic streaming in plant cells is directly visible in the cases of Chara corallina and Nitella flexilis, and this streaming is understood to play a role in the transport of biological materials. For this reason, related studies have focused on molecular transportation from a fluid mechanics viewpoint. However, the experimentally observed distribution of the velocity along the flow direction x, which exhibits two peaks at Vx = 0 and at a finite Vx(≠0), remains to be studied. In this paper, we numerically study whether this behavior of the flow field can be simulated by a 2D stochastic Navier–Stokes (NS) equation for Couette flow in which a random Brownian force is assumed. We present the first numerical evidence that these peaks are reproduced by the stochastic NS equation, which implies that the Brownian motion of the fluid particles plays an essential role in the emergence of these peaks in the velocity distribution. We also find that the position of the peak at Vx(≠0) moves with the variation in the strength D of the random Brownian force, which also changes depending on physical parameters such as the kinematic viscosity, boundary velocity, and diameter of the plant cells.

ACS Style

Vladislav Egorov; Olga Maksimova; Irina Andreeva; Hiroshi Koibuchi; Satoshi Hongo; Shinichiro Nagahiro; Toshiyuki Ikai; Madoka Nakayama; Shuta Noro; Tetsuya Uchimoto; Jean-Paul Rieu. Stochastic fluid dynamics simulations of the velocity distribution in protoplasmic streaming. Physics of Fluids 2020, 32, 121902 .

AMA Style

Vladislav Egorov, Olga Maksimova, Irina Andreeva, Hiroshi Koibuchi, Satoshi Hongo, Shinichiro Nagahiro, Toshiyuki Ikai, Madoka Nakayama, Shuta Noro, Tetsuya Uchimoto, Jean-Paul Rieu. Stochastic fluid dynamics simulations of the velocity distribution in protoplasmic streaming. Physics of Fluids. 2020; 32 (12):121902.

Chicago/Turabian Style

Vladislav Egorov; Olga Maksimova; Irina Andreeva; Hiroshi Koibuchi; Satoshi Hongo; Shinichiro Nagahiro; Toshiyuki Ikai; Madoka Nakayama; Shuta Noro; Tetsuya Uchimoto; Jean-Paul Rieu. 2020. "Stochastic fluid dynamics simulations of the velocity distribution in protoplasmic streaming." Physics of Fluids 32, no. 12: 121902.

Preprint
Published: 04 October 2019
Reads 0
Downloads 0

We report simulation results of skyrmions on fluctuating 2D lattices, where the vertices ${\bf r}_i (\in {\bf R}^3)$ are treated as a dynamical variable and, hence, there is no crystalline structure. On the fluctuating surfaces, an external magnetic field perpendicular to the surface, Dzyaloshinskii-Moriya and ferromagnetic interactions are assumed in addition to the Helfrich-Polyakov Hamiltonian for membranes. The surface (or frame) tension $\tau$ is calculated under both isotropic and uniaxial strain conditions, and this calculation clarifies a non-trivial dependence of $\tau$ on the skyrmion, stripe, and ferromagnetic phases. We find that the variation of $\tau$ with respect to the applied magnetic field in the skyrmion phase is accompanied by a variation of the total number of skyrmions. Moreover, we find that this total number variation is qualitatively consistent with a recent experimental result for the creation/annihilation of skyrmions of 3D crystalline material under uniaxial stress conditions. It is also found that the stripe phase is significantly influenced by uniaxial strains, while the skyrmion phase remains unchanged. These results allow us to conclude that the skyrmion phase is stable even on fluctuating surfaces.

ACS Style

Sahbi El Hog; Fumitake Kato; Hiroshi Koibuchi; Hung T. Diep. Skyrmions on 2D Elastic Surfaces with Fixed Boundary Frame. 2019, 1 .

AMA Style

Sahbi El Hog, Fumitake Kato, Hiroshi Koibuchi, Hung T. Diep. Skyrmions on 2D Elastic Surfaces with Fixed Boundary Frame. . 2019; ():1.

Chicago/Turabian Style

Sahbi El Hog; Fumitake Kato; Hiroshi Koibuchi; Hung T. Diep. 2019. "Skyrmions on 2D Elastic Surfaces with Fixed Boundary Frame." , no. : 1.

Journal article
Published: 11 April 2019 in Physica A: Statistical Mechanics and its Applications
Reads 0
Downloads 0

In this paper, we study the boundary effect on the surface (or frame) tension of elastic membrane surface models. The frame tension generally depends only on the projected area of the boundary over which the surface spans. However, from a spin model analogy, the frame tension is expected to be dependent also on the boundary shape at the continuous transition point. We confirm this expectation using the following fixed-connectivity and tethered surface models: the surface model of Helfrich and Polyakov and a surface model with deficit angle term. We also discuss the reason why this expectation is worthwhile to study.

ACS Style

Hiroshi Koibuchi. Surface tension of membranes depending on the boundary shape. Physica A: Statistical Mechanics and its Applications 2019, 526, 120960 .

AMA Style

Hiroshi Koibuchi. Surface tension of membranes depending on the boundary shape. Physica A: Statistical Mechanics and its Applications. 2019; 526 ():120960.

Chicago/Turabian Style

Hiroshi Koibuchi. 2019. "Surface tension of membranes depending on the boundary shape." Physica A: Statistical Mechanics and its Applications 526, no. : 120960.

Conference paper
Published: 21 December 2018 in Journal of Physics: Conference Series
Reads 0
Downloads 0

A mathematical modeling, the Finsler geometry (FG) technique, is applied to study the rubber elasticity. Existing experimental data of stress-strain (SS) diagrams, which are highly non-linear, are numerically reproduced. Moreover, the strain induced crystallization (SIC), typical of some rubbers like Natural Rubber (NR), which is known to play an important role in the mechanical property of rubbers, is partly implemented in the model. Indeed, experimentally observed hysteresis of SS curve can be reproduced if the parameter a of non-polar (or polar) interaction energy is increased for the unloading or shrinkage process in the Monte Carlo (MC) simulations, and at the same time we find that the order parameter M of the directional degrees of freedom σ of polymer show a hysteresis behavior which is compatible with that of the crystallization ratio. In addition, rupture phenomena, which are accompanied by a necking phenomenon observed in the plastic deformation region, can also be reproduced. Thus we find that the interaction implemented in the FG model via the Finsler metric is suitable in describing the mechanical property of rubbers.

ACS Style

Hiroshi Koibuchi; Chrystelle Bernard; Jean-Marc Chenal; Gildas Diguet; Gael Sebald; Jean-Yves Cavaille; Toshiyuki Takagi; Laurent Chazeau. Mathematical Modeling of Rubber Elasticity. Journal of Physics: Conference Series 2018, 1141, 012081 .

AMA Style

Hiroshi Koibuchi, Chrystelle Bernard, Jean-Marc Chenal, Gildas Diguet, Gael Sebald, Jean-Yves Cavaille, Toshiyuki Takagi, Laurent Chazeau. Mathematical Modeling of Rubber Elasticity. Journal of Physics: Conference Series. 2018; 1141 (1):012081.

Chicago/Turabian Style

Hiroshi Koibuchi; Chrystelle Bernard; Jean-Marc Chenal; Gildas Diguet; Gael Sebald; Jean-Yves Cavaille; Toshiyuki Takagi; Laurent Chazeau. 2018. "Mathematical Modeling of Rubber Elasticity." Journal of Physics: Conference Series 1141, no. 1: 012081.

Journal article
Published: 08 December 2018 in Polymers
Reads 0
Downloads 0

We numerically study surface models defined on hexagonal disks with a free boundary. 2D surface models for planar surfaces have recently attracted interest due to the engineering applications of functional materials such as graphene and its composite with polymers. These 2D composite meta-materials are strongly influenced by external stimuli such as thermal fluctuations if they are sufficiently thin. For this reason, it is very interesting to study the shape stability/instability of thin 2D materials against thermal fluctuations. In this paper, we study three types of surface models including Landau-Ginzburg (LG) and Helfirch-Polyakov models defined on triangulated hexagonal disks using the parallel tempering Monte Carlo simulation technique. We find that the planar surfaces undergo a first-order transition between the smooth and crumpled phases in the LG model and continuous transitions in the other two models. The first-order transition is relatively weak compared to the transition on spherical surfaces already reported. The continuous nature of the transition is consistent with the reported results, although the transitions are stronger than that of the reported ones.

ACS Style

Andrey Shobukhov; Hiroshi Koibuchi. Parallel Tempering Monte Carlo Studies of Phase Transition of Free Boundary Planar Surfaces. Polymers 2018, 10, 1360 .

AMA Style

Andrey Shobukhov, Hiroshi Koibuchi. Parallel Tempering Monte Carlo Studies of Phase Transition of Free Boundary Planar Surfaces. Polymers. 2018; 10 (12):1360.

Chicago/Turabian Style

Andrey Shobukhov; Hiroshi Koibuchi. 2018. "Parallel Tempering Monte Carlo Studies of Phase Transition of Free Boundary Planar Surfaces." Polymers 10, no. 12: 1360.

Preprint
Published: 26 October 2018
Reads 0
Downloads 0

We numerically study surface models defined on hexagonal disks with a free boundary. 2D surface models for planer surfaces have recently attracted interest due to the engineering applications of functional materials such as graphene and its composite with polymers. These 2D composite meta-materials are strongly influenced by external stimuli such as thermal fluctuations if they are sufficiently thin. For this reason, it is very interesting to study the shape stability/instability of thin 2D materials against thermal fluctuations. In this paper, we study three types of surface models including Landau-Ginzburg (LG) and Helfirch-Polyakov models defined on triangulated hexagonal disks using the parallel tempering Monte Carlo simulation technique. We find that the planer surfaces undergo a first-order transition between the smooth and crumpled phases in the LG model and continuous transitions in the other two models. The first-order transition is relatively weaker compared to the transition on spherical surfaces already reported. The continuous nature of the transition is consistent with the reported results, although the transitions are stronger than that of the reported ones.

ACS Style

Andrey Shobukhov; Hiroshi Koibuchi. Parallel Tempering Monte Carlo Studies of Phase Transition of Free Boundary Planar Surfaces. 2018, 1 .

AMA Style

Andrey Shobukhov, Hiroshi Koibuchi. Parallel Tempering Monte Carlo Studies of Phase Transition of Free Boundary Planar Surfaces. . 2018; ():1.

Chicago/Turabian Style

Andrey Shobukhov; Hiroshi Koibuchi. 2018. "Parallel Tempering Monte Carlo Studies of Phase Transition of Free Boundary Planar Surfaces." , no. : 1.

Journal article
Published: 11 September 2018 in Journal of Physics: Condensed Matter
Reads 0
Downloads 0

The shape transformation of liquid crystal elastomers (LCEs) under external electric fields is studied through Monte Carlo simulations of models constructed on the basis of Finsler geometry (FG). For polydomain side-chain-type LCEs, it is well known that the external-field-driven alignment of the director is accompanied by an anisotropic shape deformation. However, the mechanism of this deformation is quantitatively still unclear in some part and should be studied further from the microscopic perspective. In this paper, we evaluate whether this shape deformation is successfully simulated, or in other words, quantitatively understood, by the FG model. The FG assumed inside the material is closely connected to the directional degrees of freedom of LC molecules and plays an essential role in the anisotropic transformation. We find that the existing experimental data on the deformations of polydomain LCEs are in good agreement with the Monte Carlo results. It is also found that experimental diagrams of strain versus external voltage of a monodomain LCE in the nematic phase are well described by the FG model.

ACS Style

Evgenii Proutorov; Naoki Matsuyama; Hiroshi Koibuchi. Finsler geometry modeling and Monte Carlo study of liquid crystal elastomers under electric fields. Journal of Physics: Condensed Matter 2018, 30, 405101 .

AMA Style

Evgenii Proutorov, Naoki Matsuyama, Hiroshi Koibuchi. Finsler geometry modeling and Monte Carlo study of liquid crystal elastomers under electric fields. Journal of Physics: Condensed Matter. 2018; 30 (40):405101.

Chicago/Turabian Style

Evgenii Proutorov; Naoki Matsuyama; Hiroshi Koibuchi. 2018. "Finsler geometry modeling and Monte Carlo study of liquid crystal elastomers under electric fields." Journal of Physics: Condensed Matter 30, no. 40: 405101.

Journal article
Published: 09 July 2018 in Polymers
Reads 0
Downloads 0

In this paper, we show that the 3D Finsler geometry (FG) modeling technique successfully explains a reported experimental result: a thin liquid crystal elastomer (LCE) disk floating on the water surface deforms under light irradiation. In the reported experiment, the upper surface is illuminated by a light spot, and the nematic ordering of directors is influenced, but the nematic ordering remains unchanged on the lower surface contacting the water. This inhomogeneity of the director orientation on/inside the LCE is considered as the origin of the shape change that drives the disk on the water in the direction opposite the movement of the light spot. However, the mechanism of the shape change is still insufficiently understood because to date, the positional variable for the polymer has not been directly included in the interaction energy of the models for this system. We find that this shape change of the disk can be reproduced using the FG model. In this FG model, the interaction between σ, which represents the director field corresponding to the directional degrees of LC, and the polymer position is introduced via the Finsler metric. This interaction, which is a direct consequence of the geometry deformation, provides a good description of the shape deformation of the LCE disk under light irradiation.

ACS Style

Hiroshi Koibuchi. Bending of Thin Liquid Crystal Elastomer under Irradiation of Visible Light: Finsler Geometry Modeling. Polymers 2018, 10, 757 .

AMA Style

Hiroshi Koibuchi. Bending of Thin Liquid Crystal Elastomer under Irradiation of Visible Light: Finsler Geometry Modeling. Polymers. 2018; 10 (7):757.

Chicago/Turabian Style

Hiroshi Koibuchi. 2018. "Bending of Thin Liquid Crystal Elastomer under Irradiation of Visible Light: Finsler Geometry Modeling." Polymers 10, no. 7: 757.

Journal article
Published: 29 June 2018 in Polymers
Reads 0
Downloads 0

Herein, we study stress⁻strain diagrams of soft biological materials such as animal skin, muscles, and arteries by Finsler geometry (FG) modeling. The stress⁻strain diagram of these biological materials is always J-shaped and is composed of toe, heel, linear, and failure regions. In the toe region, the stress is almost zero, and the length of this zero-stress region becomes very large (≃150%) in, for example, certain arteries. In this paper, we study long-toe diagrams using two-dimensional (2D) and 3D FG modeling techniques and Monte Carlo (MC) simulations. We find that, except for the failure region, large-strain J-shaped diagrams are successfully reproduced by the FG models. This implies that the complex J-shaped curves originate from the interaction between the directional and positional degrees of freedom of polymeric molecules, as implemented in the FG model.

ACS Style

Kazuhiko Mitsuhashi; Swapan Ghosh; Hiroshi Koibuchi. Mathematical Modeling and Simulations for Large-Strain J-Shaped Diagrams of Soft Biological Materials. Polymers 2018, 10, 715 .

AMA Style

Kazuhiko Mitsuhashi, Swapan Ghosh, Hiroshi Koibuchi. Mathematical Modeling and Simulations for Large-Strain J-Shaped Diagrams of Soft Biological Materials. Polymers. 2018; 10 (7):715.

Chicago/Turabian Style

Kazuhiko Mitsuhashi; Swapan Ghosh; Hiroshi Koibuchi. 2018. "Mathematical Modeling and Simulations for Large-Strain J-Shaped Diagrams of Soft Biological Materials." Polymers 10, no. 7: 715.

Other
Published: 08 March 2018
Reads 0
Downloads 0

Herein, we study stress-strain diagrams of soft biological tissues such as animal skin, muscles and arteries by Finsler geometry (FG) modeling. The stress-strain diagram of these biological materials is always J-shaped and is composed of toe, heel, linear and failure regions. In the toe region, the stress is zero, and the length of this zero-stress region becomes very large (≃ 150%) in, for example, certain arteries. In this paper, we study long-toe diagrams using two-dimensional (2D) and 3D FG modeling techniques and Monte Carlo (MC) simulations. We find that except for the failure region, large-strain J-shaped diagrams are successfully reproduced by the FG models. This implies that the complex J-shaped curves originate from the interaction between the directional and positional degrees of freedom of polymeric molecules, as implemented in the FG model.

ACS Style

Kazuhiko Mitsuhashi; Swapan Ghosh; Hiroshi Koibuchi. Mathematical modeling and simulations for large-strain J-shaped diagrams of soft biological tissues. 2018, 275206 .

AMA Style

Kazuhiko Mitsuhashi, Swapan Ghosh, Hiroshi Koibuchi. Mathematical modeling and simulations for large-strain J-shaped diagrams of soft biological tissues. . 2018; ():275206.

Chicago/Turabian Style

Kazuhiko Mitsuhashi; Swapan Ghosh; Hiroshi Koibuchi. 2018. "Mathematical modeling and simulations for large-strain J-shaped diagrams of soft biological tissues." , no. : 275206.

Conference paper
Published: 01 December 2017 in Journal of Physics: Conference Series
Reads 0
Downloads 0

In this paper, a triangulated surface model is studied in the context of Finsler geometry (FG) modeling. This FG model is an extended version of a recently reported model for two-component membranes, and it is asymmetric under surface inversion. We show that the definition of the model is independent of how the Finsler length of a bond is defined. This leads us to understand that the canonical (or Euclidean) surface model is obtained from the FG model such that it is uniquely determined as a trivial model from the viewpoint of well definedness.

ACS Style

Evgenii Proutorov; Hiroshi Koibuchi. Finsler Geometry Modeling of an Orientation-Asymmetric Surface Model for Membranes. Journal of Physics: Conference Series 2017, 936, 12038 .

AMA Style

Evgenii Proutorov, Hiroshi Koibuchi. Finsler Geometry Modeling of an Orientation-Asymmetric Surface Model for Membranes. Journal of Physics: Conference Series. 2017; 936 (1):12038.

Chicago/Turabian Style

Evgenii Proutorov; Hiroshi Koibuchi. 2017. "Finsler Geometry Modeling of an Orientation-Asymmetric Surface Model for Membranes." Journal of Physics: Conference Series 936, no. 1: 12038.

Article
Published: 26 April 2017 in Physical Review E
Reads 0
Downloads 0

We present Monte Carlo data of the stress-strain diagrams obtained using two different triangulated surface models. The first is the canonical surface model of Helfrich and Polyakov (HP), and the second is a Finsler geometry (FG) model. The shape of the experimentally observed stress-strain diagram is called J-shaped. Indeed, the diagram has a plateau for the small strain region and becomes linear in the relatively large strain region. Because of this highly nonlinear behavior, the J-shaped diagram is far beyond the scope of the ordinary theory of elasticity. Therefore, the mechanism behind the J-shaped diagram still remains to be clarified, although it is commonly believed that the collagen degrees of freedom play an essential role. We find that the FG modeling technique provides a coarse-grained picture for the interaction between the collagen and the bulk material. The role of the directional degrees of freedom of collagen molecules or fibers can be understood in the context of FG modeling. We also discuss the reason for why the J-shaped diagram cannot (can) be explained by the HP (FG) model.

ACS Style

Yu Takano; Hiroshi Koibuchi. J-shaped stress-strain diagram of collagen fibers: Frame tension of triangulated surfaces with fixed boundaries. Physical Review E 2017, 95, 042411 .

AMA Style

Yu Takano, Hiroshi Koibuchi. J-shaped stress-strain diagram of collagen fibers: Frame tension of triangulated surfaces with fixed boundaries. Physical Review E. 2017; 95 (4):042411.

Chicago/Turabian Style

Yu Takano; Hiroshi Koibuchi. 2017. "J-shaped stress-strain diagram of collagen fibers: Frame tension of triangulated surfaces with fixed boundaries." Physical Review E 95, no. 4: 042411.

Journal article
Published: 25 April 2017 in Axioms
Reads 0
Downloads 0

We study triangulated surface models with nontrivial surface metrices for membranes. The surface model is defined by a mapping r from a two-dimensional parameter space M to the three-dimensional Euclidean space R3. The metric variable gab, which is always fixed to the Euclidean metric δab, can be extended to a more general non-Euclidean metric on M in the continuous model. The problem we focus on in this paper is whether such an extension is well defined or not in the discrete model. We find that a discrete surface model with a nontrivial metric becomes well defined if it is treated in the context of Finsler geometry (FG) modeling, where triangle edge length in M depends on the direction. It is also shown that the discrete FG model is orientation asymmetric on invertible surfaces in general, and for this reason, the FG model has a potential advantage for describing real physical membranes, which are expected to have some asymmetries for orientation-changing transformations.

ACS Style

Evgenii Proutorov; Hiroshi Koibuchi. Orientation Asymmetric Surface Model for Membranes: Finsler Geometry Modeling. Axioms 2017, 6, 10 .

AMA Style

Evgenii Proutorov, Hiroshi Koibuchi. Orientation Asymmetric Surface Model for Membranes: Finsler Geometry Modeling. Axioms. 2017; 6 (4):10.

Chicago/Turabian Style

Evgenii Proutorov; Hiroshi Koibuchi. 2017. "Orientation Asymmetric Surface Model for Membranes: Finsler Geometry Modeling." Axioms 6, no. 4: 10.

Preprint
Published: 20 April 2017
Reads 0
Downloads 0

We study triangulated surface models with nontrivial surface metrices for membranes. The surface model is defined by a mapping ${\bf r}$ from a two dimensional parameter space $M$ to the three dimensional Euclidean space ${\bf R}^3$. The metric variable $g_{ab}$, which is always fixed to the Euclidean metric $\delta_{ab}$, can be extended to a more general non-Euclidean metric on $M$ in the continuous model. The problem we focus on in this paper is whether such an extension is well-defined or not in the discrete model. We find that a discrete surface model with nontrivial metric becomes well-defined if it is treated in the context of Finsler geometry (FG) modeling, where triangle edge length in $M$ depends on the direction. It is also shown that the discrete FG model is orientation assymetric on invertible surfaces in general, and for this reason, the FG model has a potential advantage for describing real physical membranes, which are expected to have some assymetries for orientation changing transformations.

ACS Style

Evgenii Proutorov; Hiroshi Koibuchi. Orientation Asymmetric Surface Model for Membranes: Finsler Geometry Modeling. 2017, 1 .

AMA Style

Evgenii Proutorov, Hiroshi Koibuchi. Orientation Asymmetric Surface Model for Membranes: Finsler Geometry Modeling. . 2017; ():1.

Chicago/Turabian Style

Evgenii Proutorov; Hiroshi Koibuchi. 2017. "Orientation Asymmetric Surface Model for Membranes: Finsler Geometry Modeling." , no. : 1.

Original articles
Published: 17 February 2017 in Ferroelectrics
Reads 0
Downloads 0

We study numerically elongation phenomena of flexible materials, such as liquid crystal (LC) elastomers (or ferroelectric polymers FEP), under external electromagnetic fields using Finsler geometry (FG) model. In this model, the interaction between LC molecules (or monomers) and the bulk material is implemented in the Finsler metric, the elements of which are considered to be dependent on the LC molecule direction (or the polarization of monomers in FEP). We have found out from Monte Carlo data that dependence of strain versus external field is consistent with existing experimental data.

ACS Style

H. Koibuchi. Finsler geometry modeling of elongation of flexible materials under external electromagnetic field. Ferroelectrics 2017, 508, 144 -150.

AMA Style

H. Koibuchi. Finsler geometry modeling of elongation of flexible materials under external electromagnetic field. Ferroelectrics. 2017; 508 (1):144-150.

Chicago/Turabian Style

H. Koibuchi. 2017. "Finsler geometry modeling of elongation of flexible materials under external electromagnetic field." Ferroelectrics 508, no. 1: 144-150.

Journal article
Published: 04 August 2016 in Polymers
Reads 0
Downloads 0

A Finsler geometric surface model is studied as a coarse-grained model for membranes of three components, such as zwitterionic phospholipid (DOPC), lipid (DPPC) and an organic molecule (cholesterol). To understand the phase separation of liquid-ordered (DPPC rich) Lo and liquid-disordered (DOPC rich) Ld, we introduce a binary variable σ(=±1) into the triangulated surface model. We numerically determine that two circular and stripe domains appear on the surface. The dependence of the morphological change on the area fraction of Lo is consistent with existing experimental results. This provides us with a clear understanding of the origin of the line tension energy, which has been used to understand these morphological changes in three-component membranes. In addition to these two circular and stripe domains, a raft-like domain and budding domain are also observed, and the several corresponding phase diagrams are obtained.

ACS Style

Satoshi Usui; Hiroshi Koibuchi. Finsler Geometry Modeling of Phase Separation in Multi-Component Membranes. Polymers 2016, 8, 284 .

AMA Style

Satoshi Usui, Hiroshi Koibuchi. Finsler Geometry Modeling of Phase Separation in Multi-Component Membranes. Polymers. 2016; 8 (8):284.

Chicago/Turabian Style

Satoshi Usui; Hiroshi Koibuchi. 2016. "Finsler Geometry Modeling of Phase Separation in Multi-Component Membranes." Polymers 8, no. 8: 284.

Journal article
Published: 12 May 2016 in International Journal of Modern Physics C
Reads 0
Downloads 0
ACS Style

Hiroshi Koibuchi; Andrey Shobukhov. Erratum:"Internal phase transition induced by external forces in Finsler geometric model for membranes". International Journal of Modern Physics C 2016, 27, 1692001 .

AMA Style

Hiroshi Koibuchi, Andrey Shobukhov. Erratum:"Internal phase transition induced by external forces in Finsler geometric model for membranes". International Journal of Modern Physics C. 2016; 27 (5):1692001.

Chicago/Turabian Style

Hiroshi Koibuchi; Andrey Shobukhov. 2016. "Erratum:"Internal phase transition induced by external forces in Finsler geometric model for membranes"." International Journal of Modern Physics C 27, no. 5: 1692001.

Conference paper
Published: 22 April 2016 in MATEC Web of Conferences
Reads 0
Downloads 0

In this paper, we study a surface model for membranes of three components such as DPPC, DOPC, and Cholesterol. This membrane is experimentally well known to undergo the phase separation and to form the domain structure such as the liquid ordered (Lo) phase and the liquid disordered phase (Ld). It is also well known that this multicomponent membrane has a lot of domain pattern transitions between the circular domains and the striped domain etc. Using the new surface model constructed on the basis of Finsler geometry, we study why those morphological changes appear on the spherical vesicles. In our model, we introduce a new variable σ (∈Z2 to represent the domains Lo and Ld , and using the value of σ we define a metric function on the surface. As a consequence, the origin of the line tension energy, which has been used to explain the domain pattern transition in the multicomponent membranes, is naturally understood in our model.

ACS Style

Satoshi Usui; Hiroshi Koibuchi. Phase Separation and Domain Formation in Multi-Component Membranes: Finsler Geometry Modeling and Monte Carlo Simulations. MATEC Web of Conferences 2016, 54, 1002 .

AMA Style

Satoshi Usui, Hiroshi Koibuchi. Phase Separation and Domain Formation in Multi-Component Membranes: Finsler Geometry Modeling and Monte Carlo Simulations. MATEC Web of Conferences. 2016; 54 ():1002.

Chicago/Turabian Style

Satoshi Usui; Hiroshi Koibuchi. 2016. "Phase Separation and Domain Formation in Multi-Component Membranes: Finsler Geometry Modeling and Monte Carlo Simulations." MATEC Web of Conferences 54, no. : 1002.