NbSe3:Effect of uniaxial stress on the threshold field and fermiology

Abstract

We have measured the effect of elastic strain ǫ on the threshold field ET for the motion of the higher temperature charge density wave(CDW) in NbSe3. We find that ET exhibits a critical behavior, ET ∼ (1 − ǫ/ǫc) γ where ǫc is about 2.6%, γ ∼1.2. This expression remains valid over more than two decades of ET , up to the highest fields of about 1.5 kV/m measured using pulse techniques. Neither γ nor ǫc is very sensitive to the impurity content of the sample. The transition temperature is linear with ǫ, and dTP /dǫ = 10 K/% shows no anomaly near ǫc. The slope of the narrow band noise frequency vs. the CDW current does not change appreciably with ǫ. Shubnikov-de Haas measurements show that the extremal area of the Fermi surface decreases with increasing ǫ. We conclude that there is a very intimate relationship between pinning and the Fermiology in NbSe3.

Controlling the metal-to-insulator relaxation of the metastable hidden quantum state in 1T-TaS 2

“…Furthermore, the contacts at the edges of the sample provide boundary conditions at which the CDW is pinned. A change of dimensions induced by strain requires a rearrangement of the CDW, which proceeds in a quantized fashion, leading to resistance steps as previously shown in K 0.3 MoO 3 ( 34 ), whereas the possible effect of strain on the commensurability was discussed in NbSe 3 ( 35 ). If we assume that the H state is qualitatively similar to the NC state with a distance of ~8 nm between domain walls, a strain of 0.2% over a distance of 1 to 10 μm between contacts introduces about one to two extra domain walls in each in-plane direction.…”

Magnetic field mediated charge density wave transport in Ni doped NbSe3 nanowires

“…The possible new CDW states may be induced by certain disorder or strain introduced during magnetization, accompanied by a rearrangement of the local CDW order proceeding in a quantized fashion, which leads to resistance steps as previously observed in K 0.3 MoO 3 31 and NbSe 3 . 8, 32 In details, the metallic state of Ni doped NbSe 3 is not thermodynamically stable below room temperature. We can drive a transition toward the thermodynamically stable state, state at and state at if we apply an in-plane current after cooling the sample in equilibrium.…”

Topological effects of charge density waves in ring-shaped crystals ofNbSe3

“…It is possible that the strain energy of the crystal was changed by the change of topology. 25 However, the strain energy of the remaining path was not changed by the surgery because the sample was fixed at two points on a sapphire plate by silver paste. We therefore considered the effect of the edges or the interaction between the two current paths.…”