Single-crystal rings of NbSe3: a system for CDW interference?

We have produced new ring- and tube-shaped crystals of NbSe3 and found repr oducible synthesizing conditions. We have confirmed that the ring is a sing le-phase NbSe3 crystal from X-ray diffraction, and that a charge-density wa ve (CDW) transition takes place near 140 K by observing satellites of elect ron diffraction peaks. The position of the satellites coincides with that o f the conventional NbSe3 at the CDW transition. Non-linear conduction due t o the CDW sliding is also observed in the ring crystals. The threshold fiel d is similar to the conventional ribbon-shaped NbSe3 crystals. (C) 2000 Pub lished by Elsevier Science B.V. All rights reserved.