Currents conversion in the submicron CDW-N-CDW structures

Using selective area irradiation by electrons with high energies the submicron CDW-N -CDW heterostructures were obtained on NbSe, single crystals. In sliding CDW regime an excess voltage appears on this narrow normal region that depends neither on a sample, nor on the length of the irradiated area l and represents threshold phase slip (PS) voltage V$_{\rm ps}$, induced on CW-N boundaries. The obtained V$_{\rm ps}$, data for lower CDW strongly differ (5-6 times higher) from the known results for NbSe, obtained in the conventional configuration. This suggests that CDW-N boundaries created by irradiation represent the "ideal" face contacts introducing small perturbations. At low temperature (T$<$7 K) and at l$<$0.5 $\mu$m we observe narrow ($-0.5$ mV width) dynamic conductance peak at zero bias voltage. The peak amplitude grows with decreasing temperature and length of the irradiated area

Point-contact spectroscopy of quasi-1D conductors with CDW

The nature of carrier reflection from a normal metal-Peierls conductor interface is clarifiecl by studying both the characteristics of direct point contacts Au-NbSe3 (K0.3MoO3) oriental along the chains, and point contacts formed with an intermediate metallic layer sputtered onto the K0.3MoO3 crystals. In the Peierls state, for bias voltages eV smaller than the Peierls gap Δp, an excess differential resistance is observed for both experimental configuration. The dominant contribution to the excess resistance for injection along the chains is from normal reflection of carriers without changes in the sign of their charge and a momentum transfer 2pF to the condencate of electron-hole pairs carried away from the interface. For Au-K0.3MoO3 contacts the character of nonlinearity and the observed asymmetric features of the IV characteristics indicate that a substantial shift of the chemical potential occurs near the boundary with the normal metal

Variable-range-hopping-like transverse conductivity of the quasi one-dimensional conductor TaS3_{3}

We report temperature dependence of transverse conductivity and its hysteresis in TaS$_3$. The results argue that the conductivity mechanism is variable-range hopping (VRH)

The In-plane anisotropy of the hall anomaly in BSCCO whiskers

The Hall effect in single crystal BSCCO whiskers has been measured, with the current flowing along the a and b crystallographic directions. The ab-plane anisotropy of the Hall anomaly is found. The magnitude of the anomaly, as well as its anisotropy, are strongly affected by the structural defects. © 2005 Springer Science+Business Media, Inc

On the critical current for the charge density wave transport

We report transport measurements under very high current densities $j$, up to $10^8$ A/cm$^2$, of quasi-one-dimensional charge-density wave (CDW) conductors NbSe$_3$ and TaS$_3$. Above $j_0-10^1$ A/cm$^2$ the point contacts NbSe$_3$-NbSe$_3$ show a sharp singularity, and the TaS$_3$ nanosamples show metallic temperature dependence (positive d$R$/d$n$. We interpret both results as an evidence for the suppression of the Peierls gap 2A and development of the metallic state above $j_0$. Possible scenarios of the Peierls state destruction are discussed