Investigation of Elastic Effects of Sliding Charge-density Waves


Book Description

The elastic softening associated with the sliding of a charge-density wave (CDW), driven by an electric field, is investigated in o-TaS$sb3$ by use of a vibrating-reed technique. Experiments performed with a dc sliding CDW find the magnitude of the change in Young's modulus, Y, to be proportional to the square of the CDW order parameter and to be independent of pinning strength, in agreement with most theories regarding the phenomenon. The fractional portion of the softening realized at any given field is found to be controlled by the current transported by the CDW. Analysis is presented showing the softening for dc sliding to be consistent with relaxation involving a broad distribution of characteristic times. This distribution is correlated to that for the dielectric function of the stationary state, providing evidence that the pinning forces are not fundamentally different between the stationary and sliding states. Experiments where the CDW was driven by an ac electric field, switched at a frequency f$sb{rm I}$ from 1 Hz to MHz, showed a non-monotonic dependence of the degree of softening on f$sb{rm I}$ near 10 kHz accompanied by a peak in internal friction, and recovery of Y towards its value for a stationary CDW at higher frequency. Simultaneously, the amplitude of the overshoot phenomenon was seen to decrease with f$sb{rm I}$. Such findings indicate the presence of slow dynamical processes which are though to involve relaxations of the CDW phase configuration. The non-monotonic behavior of Y at intermediate frequency is speculated to be due to availability of new relaxational modes not accessible to the dc sliding CDW.




Charge Density Waves in Solids


Book Description

The latest addition to this series covers a field which is commonly referred to as charge density wave dynamics. The most thoroughly investigated materials are inorganic linear chain compounds with highly anisotropic electronic properties. The volume opens with an examination of their structural properties and the essential features which allow charge density waves to develop. The behaviour of the charge density waves, where interesting phenomena are observed, is treated both from a theoretical and an experimental standpoint. The role of impurities in statics and dynamics is considered and an examination of the possible role of solitons in incommensurate charge density wave systems is given. A number of ways to describe charge density waves theoretically, using computer simulations as well as microscopical models, are presented by a truely international board of authors.




Charge Density Waves in Solids


Book Description

Neutron and x-ray scattering study on K0.3MoO3 and other quasi one dimensional conductors -- X-ray study of charge-density wave in K0.30Mo03 under electric fields -- Transmission electron microscopy for imaging and diffraction studies of low dimensional transition metal chalcogenides -- Aspects of charge-density waves in the TaTe4-NbTe4 structures and in 2H-TaSe2 -- Charge density waves, phasing, sliding and related phenomena in NbSe3 and other transition metal chalcogenides -- Structural and electrical properties interpretation through band structure calculations on the (MSe4)nI SERIES (M = Nb, Ta). -- Defects and charge density waves in irradiated layer and chain compounds -- Electron diffraction charge density wave studies in the chalcogenide compounds (MX4)nI -- Neutron studies of the blue bronzes K0.3MoO3 and Rb0.3MoO3 -- The effect of a magnetic field on the discotm1ensurate to commensurate transition in 2H TaSe2 -- High pressure investigation of the cdw phase diagram of 1T-TaS2 -- Landau theory of 2H-TaSe2 -- Multidomain structures of incommensurate phases in CDW states of 2H-TaSe2 -- Electron microscopy of charge density wave defects in 1T-TaS2 and 1T-TaSe2 -- Aspects of strong electron-phonon coupling related to the CDW transition at temperatures above it -- Elastic and other properties at the commensurate-incommensurate transition in 2H-TaSe2 -- CDW phase mode investigation in the FIR in K0.3MaO3 and band structure calculation -- 93Nb NMR study of CDW in (NbSe4)10/3I single crystal -- Electronic Properties and Fe57 Mössbauer measurements of T1+xNb3-xSe10 with T = Fe, Cr -- Transport and Mössbauer studies of the peierls transition in Fe-doped K0.30MoO3 -- Charge density wave instabilities in quasi two-dimensional oxides n-Mo4O11 and ?-Mo4O11 -- Thermal conductivity of layered dichalcogenides -- Tunneling study of commensurate charge density wave states in 1T-TaS2 -- Galvanomagnetic properties of the quasi-two dimensional purple bronze K0.9Mo6O17 -- Non-local elastic forces in charge-density wave systems -- Soliton model of charge-density-wave depinning -- Dynamics of incommensurate structures -- Some problems arising from electrostatic potential in CDW behavior -- The single domain model of charge-density wave transport -- On the microscopic theory of kinetic phenomena in peierls conductors -- Near commensurability effects on charge density wave dynamics -- Shift in the longitudinal sound velocity due to sliding charge density waves -- Microscopic local mechanisms for "Noises" generated by moving CDW -- Phase vortices and CDW conduction noise -- Damping of CDW-condensate motion by interaction with thermal phasons -- Microscopic theory of interaction of CDW with impurities -- Quantum effects in the Josephson approach to a CDW -- Fokker planck theory of the classical charge density wave model with current noise -- Travelling charge density waves : A mean field treatment -- Coherent and incoherent effects in charge density wave transport -- Threshold field, electrical conductivity and time-dependent voltage in transition metal tri- and tetrachalcogenides -- Solitons in TaS3 experiment -- Thermal gradient experiments on the charge-density-wave conduction noise spectrum -- Broadband noise in orthorhombic TaS3 -- High field I-V characteristics of orthorhombic TaS3 -- Inertial dynamics of CDW transport in NbSe3 -- Frequency dependent conductivity of CDW compounds -- AC conductivity of the blue bronze K0.3 MoO3 -- Subharmonic shapiro steps, devil's staircase, and synchronization in RF-driven CDW conductors -- Mode locking and chaos in sliding charge-density-wave systems -- Chaos in charge density wave systems -- Contribution of CDW motion to the hall effect and to the transverse conductivity in TaS3. experiment -- Contribution of CDW motion to the hall effect and to the transverse conductivity. Theory -- Dependence of the elastic modulus of TaS3 on the CDW current -- Low frequency elastic properties of materials containing a sliding CDW -- The conductivity of orthorhombic TaS3 under uniaxial strain -- Ohmic and nonlinear transport of (TaSe4)2I under pressure -- Pinning, metastability and sliding of charge-density-waves -- Distortion, metastability and breaking in charge-density wave transport: Recent experiments on niobium triselenide, suggesting a new mean-field approach -- Bistable configurations of the pinned charge density wave: Random-field-model dynamics observed in rearrangement prior to depinning -- Electric field induced relaxation of metastable states in TaS3 -- Remanent deformation of CDWs -- Relaxation of the deformed cdw state: electric and thermal hysteresis -- Thermal hysteresis in the thermopower of o-TaS3 -- Delayed switching between normal and CDW conducting states in o-TaS3 -- The effect of uniaxial strain on metastable states in TaS3 -- Influence of defects on the metastable states of o-TaS3 -- Charge density wave transport in the blue bronzes K0.30MoO3 and Rb0.30MoO3 : metastability, hysteresis and memory effects -- Effects of irradiation on the blue bronzes K0.30MoO3 and Rb0.30MoO3 -- Relaxation of metastable states in blue bronze K0.3MoO3 -- Incommensurate ferroelectrics -- Commensurate and incommensurate phases of a two-dimensional lattice of superconducting vortices -- (TMTSF)2X compounds: Superconductivity, spin-density waves and anion ordering -- Impurity pinning in quasi-1D superconductivity -- Numerical studies of the effect of a wall on SDW in a jellium -- Pinning of amplitude solitons in Peierls systems with impurities -- New resistive state in low dimensional superconductor TaSe3 -- Switching in cdw systems and in V02 -- A comparative study -- The effect of varying the bandfilling in a Peierls conductor -- Solitons and polarons in a spin density wave chain -- Charge density waves in superionic conductors -- Numerical study of impurity pinning in one-dimensional interacting electron systems -- Multivalued charge-density waves.




Perspectives In Physical Acoustics - Proceedings Of The Bolef Symposium


Book Description

This Symposium was held in honor of the 70th birthday of Dan Bolef, Professor Emeritus at Washington University, who joined the physics department in 1963. The articles in this volume are by internationally known and active leaders in the area of physical acoustics who were selected on the basis of their pedagogical skills as well as their stature within the field. This book provides a broad coverage of acoustics science and is sufficiently clear and pedagogical.













Handbook of Elastic Properties of Solids, Liquids, and Gases, Four-Volume Set


Book Description

Sound waves propagate through galactic space, through two-dimensional solids, through biological systems, through normal and dense stars, and through everything that surrounds us; the earth, the sea, and the air. We use sound to locate objects, to identify objects, to understand processes going on in nature, to communicate, and to entertain. The elastic properties of materials determine the velocity of sound in them and tell us about their response to stresses something which is very important when we are trying to construct, manufacture, or create something with any material. The Handbook of Elastic Properties of Materials will provide these characteristics for almost everything whose elastic properties has ever been measured or deduced in a concise and approachable manner. Leading experts will explain the significance of the elastic properties as they relate to intrinsic microscopic behavior, to manufacturing, to construction, or to diagnosis. They will discuss the propagation of sound in newly discovered or created materials, and in common materials which are being investigated with a fresh outlook. The Handbook will provide the reader with the elastic properties of the common and mundane, the novel and unique, the immense and the microscopic, and the exhorbitantly dense and the ephemeral.. You will also find the measurement. And theoretical techniques that have been developed and invented in order to extract these properties from a reluctant nature and recalcitrant systems. Key Features * Solids, liquids and gases covered in one handbook * Articles by experts describing insights developed over long and Illustrious careers * Properties of esoteric substances, such as normal and dense stars, superfluid helium three, fullerness, two dimensional solids, extraterrestial substances, gems and planetary atmospheres * Properties of common materials such as food, wood used for musical instruments, paper, cement, and cork * Modern dynamic elastic properties measurement techniques




The Summary of Engineering Research


Book Description




Charge Density Waves in Solids


Book Description

The latest addition to this series covers a field which is commonly referred to as charge density wave dynamics.The most thoroughly investigated materials are inorganic linear chain compounds with highly anisotropic electronic properties. The volume opens with an examination of their structural properties and the essential features which allow charge density waves to develop.The behaviour of the charge density waves, where interesting phenomena are observed, is treated both from a theoretical and an experimental standpoint. The role of impurities in statics and dynamics is considered and an examination of the possible role of solitons in incommensurate charge density wave systems is given. A number of ways to describe charge density waves theoretically, using computer simulations as well as microscopical models, are presented by a truely international board of authors.