| Autor: |
Nagasawa, Mitsuharu, Nagasawa, Mitsuharu |
| Zdroj: |
Journal de Physique I; December 1996, Vol. 6 Issue: 12 p2135-2140, 6p |
| Abstrakt: |
Voltage response to constant unipolar pulse current in the spin-density wave (SDW) state of (TMTSF)2AsF6was studied. Below 3 K, leading and tailing edges of the voltage response are rounded at low electric field. The time dependent charge density accumulated in the lattice was estimated from the voltage profiles. It can be fitted by a stretched exponential formula; $q(t)\propto q_0 (1-{\rm exp}(-(t/\tau_1)^\beta))$. With increasing field q0increases and shows a maximum at the threshold electric field for depinning. In the pinned state, the relaxation time $\tau_1$increases with decreasing temperature and its activation energy is approximately equal to that of ohmic conductivity. The index βis a linearly decreasing function of temperature and it is extrapolated to one at 0 K. Screening by normal carriers becomes imperfect and coupling between density wave domains becomes stronger on cooling. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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