Non-linear rheology of layered systems - a phase model approach (2007)
Yoshino, Hajime, Matsukawa, Hiroshi, Yukawa, Satoshi, Kawamura, Hikaru
We study non-linear rheology of a simple theoretical model developed to mimic layered systems such as lamellar structures under shear. In the present work we study a 2-dimensional version of the...
Goryo, Jun, Soma, Singo, Matsukawa, Hiroshi
We propose a new stage of confiment-decofinment transition, which can be observed in laboratory. In two-gap superconductors (SCs), two kinds of vortex exist and each of them carries a continuously...
Coupled Oscillators in Quenched Random Potential (2006)
Nogawa, Tomoaki, Yoshino, Hajime, Matsukawa, Hiroshi
We study a synchronization of coupled oscillators in quenched random potential by numerical simulations as a model of sliding charge density waves and flux line lattices. By changing external driving...
Coupled Oscillators in Quenched Random Potential (2006)
Nogawa, Tomoaki, Yoshino, Hajime, Matsukawa, Hiroshi
We study a synchronization of coupled oscillators in quenched random potential by numerical simulations as a model of sliding charge density waves and flux line lattices. By changing external driving...
Coupled Oscillators in Quenched Random Potential (2006)
Nogawa, Tomoaki, Yoshino, Hajime, Matsukawa, Hiroshi
We study a synchronization of coupled oscillators in quenched random potential by numerical simulations as a model of sliding charge density waves and flux line lattices. By changing external driving...
Possibility of the Solid-Fluid Transition in Moving Periodic Systems (2005)
Nogawa, Tomoaki, Yoshino, Hajime, Matsukawa, Hiroshi
The steady sliding state of periodic structures such as charge density waves and flux line lattices is numerically studied based on two and three dimensional driven random field XY models. We focus...
Flux flow resistivity in the two-gap superconductivity (2005)
Goryo, Jun, Matsukawa, Hiroshi
We investigate the flux flow state in a two-gap superconductor in which two s-wave gaps with different amplitudes exist on two separate Fermi surfaces. The flux flow resistivity is obtained on the...
Flux flow resistivity in the system with multiple superconducting gaps (2004)
Goryo, Jun, Matsukawa, Hiroshi
We calculate the flux flow resistivity in a superconductor with multiple s-wave superconducting gaps. Our result agrees well with anomalous field dependence of the resistivity recently observed in...
Atomic scale friction between clean graphite surfaces (2003)
Matsushita, Katsuyoshi, Matsukawa, Hiroshi, Sasaki, Naruo
We investigate atomic scale friction between clean graphite surfaces by using molecular dynamics. The simulation reproduces atomic scale stick-slip motion and low frictional coefficient, both of...
Kawaguchi, Takaaki, Matsukawa, Hiroshi
Frictional phenomena of two-dimensional elastic lattices are studied numerically based on a two-dimensional Frenkel-Kontorova model with impurities. It is shown that impurities can assist the...
Impurity Effects on Quantum Depinning of Commensurate Charge Density Waves (2000)
Yumoto, Masanori, Fukuyama, Hidetoshi, Matsukawa, Hiroshi, Nagaosa, Naoto
We investigate quantum depinning of the one-dimensional (1D) commensurate charge-density wave (CDW) in the presence of one impurity theoretically. Quantum tunneling rate below but close to the...
Anomalous pinning behavior in an incommensurate two-chain model of friction (1998)
Kawaguchi, Takaaki, Matsukawa, Hiroshi
Pinning phenomena in an incommensurate two-chain model of friction are studied numerically. The pinning effect due to the breaking of analyticity exists in the present model. The pinning behavior is,...
Effects of Dissipation on Quantum Phase Slippage in Charge Density Wave Systems (1998)
Miyake, Hiroyuki, Matsukawa, Hiroshi
We study the effect of the dissipation on the quantum phase slippage via the creation of ``vortex ring'' in charge density wave (CDW) systems. The dissipation is assumed to come from the interaction...
Effect of Local Inhomogeneity on Nucleation; Case of Charge Density Wave Depinning (1998)
Yumoto, Masanori, Fukuyama, Hidetoshi, Matsukawa, Hiroshi
The spatial inhomogeneities are expected to affect nucleation process in an essential way. These effects are studied theoretically by considering the case of the depinning of the charge density wave...
Dissipation Enhanced Asymmetric Transport in Quantum Ratchets (1997)
Tatara, Gen, Kikuchi, Macoto, Yukawa, Satoshi, Matsukawa, Hiroshi
Quantum mechanical motion of a particle in a periodic asymmetric potential is studied theoretically at zero temperature. It is shown based on semi-classical approximation that the tunneling...
Dynamical frictional phenomena in an incommensurate two-chain model (1997)
Kawaguchi, Takaaki, Matsukawa, Hiroshi
Dynamical frictional phenomena are studied theoretically in a two-chain model with incommensurate structure. A perturbation theory with respect to the interchain interaction reveals the contributions...
Kawaguchi, Takaaki, Matsukawa, Hiroshi
Static and dynamic frictional phenomena at the interface with random impurities are investigated in a two-chain model with incommensurate structure. Static frictional force is caused by the impurity...
Yukawa, Satoshi, Kikuchi, Macoto, Tatara, Gen, Matsukawa, Hiroshi
The concept of thermal ratchets is extended to the system governed by quantum mechanics. We study a tight-binding model with an asymmetric periodic potential contacting with a heat bath under an...
Theoretical Study of Friction: A Case of One-Dimensional Clean Surfaces (1994)
Matsukawa, Hiroshi, Fukuyama, Hidetoshi
A new method has been proposed to evaluate the frictional force in the stationary state. This method is applied to the 1-dimensional model of clean surfaces. The kinetic frictional force is seen to...
NANOSCALE EFFECTS OF SURFACES AND LUBRICANTS ON FRICTION
TAKAAKI KAWAGUCHI, HIROSHI MATSUKAWA
Nanoscale frictional phenomena at solidâsolid surfaces with lubricants are studied numerically using a lattice model which consists of two rigid substrates and a monolayer of lubricant molecules....