No abstract available

[en] Response of the spin-density wave condensate in (TMTSF)₂AsF₆ and motion of twin boundaries in (TMTSF)₂PF₆ were studied comparatively. In the former, internal degrees of fredom are essential to understand various dynamical properties. The dynamics of twin boundary is so complicated but it should not be regarded as a rigid planar object

No abstract available

[en] Dynamics of twin boundary mechanically introduced into crystals of (TMTSF)₂X was studied. Repeated motion of isolated twin boundary was observed under constant external force in the same area was observed with controlled conditions. Effect of various controlling factors as well as of temperature is discussed. (orig.)

[en] TaS₃ exhibits the metal-semiconductor transition at 218 K due to the Peierls instability. The electrical resistance was measured under pressure. It was found that both the transition temperature, Tsub(p), and the activation energy at T = 0 K, Δ(0), decrease with pressure, while the ratio, Δ(0)/Tsub(p), is independent of pressure. (author)

[en] The transition-metal trichalcogenide, TaS₃, with an orthorhombic structure was found to undergo a metal-semiconductor transition at 270 K. Electron diffraction reveals diffuse scattering above room temperature and superlattice spots at a lower temperature. These phenomena are interpreted in terms of Peierls transition. (author)

[en] We observed the current-voltage relation in the spin-density wave (SDW) phase of sightly pressurized (TMTSF)₂AsF₆ above 0.6 K to investigate the SDW dynamics. In the entire temperature range below a transition temperature of ∼ 10 K, the ohmic and non-ohmic regions are clearly distinguished by the well-defined threshold electric field. The SDW dynamics show anomalies at ∼ 3 K and, only below ∼ 3 K, 'transient voltage oscillation', 'narrow band noise' and dielectric voltage response for constant pulse current can be observed. In (TMTSF)₂PF₆, the sub-phase transitions at ∼ 3 K and ∼ 1 K have been reported. Relations between the SDW dynamics and the sub-phase transitions are discussed

[en] Orthorhombic and monoclinic polytypes of ZrTe₅ are examined by X-ray camera techniques at room temperature. Long period modulation of the former was determined. Lattice parameters of the monoclinic polytype are given. Two peaks are observed in the heat capacity of the orthorhombic crystal. One is assigned to a phase transition in the monoclinic inclusion. Another peak at 135K appears as the result of thermal excitation of electrons in a semimetallic energy band. (Auth.)

[en] Metal-to-insulator transition temperature (T_MI) and the activation energy (E_A) in the SDW phase of (TMTSF)₂AsF₆ and (TMTSF)₂PF₆ were determined under pressure. Pressure dependence of 2E_A/k_BT_MI near the critical pressure of the SDW phase, is compared with the mean-field theory by Yamaji. It was found that T_MI is not equal to the normal-to-SDW transition temperature but lower than T_SDW. Non-linear conduction was observed in a narrow temperature range above T_MI. (orig.)

[en] Transient voltage oscillation was observed in the spin-density wave phase of (TMTSF)₂AsF₆. Its frequency is proportional to the non-ohmic current. In high electric field, current-field relation becomes irregular and transient oscillation diminishes. The bistability of the density-wave conductivity proposed by Littlewood is likely to be realized. (orig.)