X-ray Correlation Spectroscopy Investigations of the Charge-density Wave Depinning Transition in pure NbSe3.
Abstract
We report synchrotron based x-ray scattering and electronic transport measurements of the charge density wave (CDW) depinning transition in pure NbSe_3. Coherent x-rays provided at the 8-ID beam-line at the Advanced Photon Source enabled the implementation of the X-ray Photon Correlation Spectroscopy technique to wide angles in order to investigate the dynamics of both the pinned and sliding CDW states. Our measurements show that the sharp zero-field cooled state speckle pattern smears and broadens as increased current depins the CDW. Subsequent reduction in the applied field results in a sharpened speckle pattern that does not regain the sharpness of the zero-field cooled state. The gradual change in the speckle pattern through depinning, rather than an expected abrupt change at the threshold field as well as the high field behavior pose areas for further investigation. This work is supported by the NSF (DMR-0102677).
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARV12013S