相关论文: Magnetization, Nernst effect and vorticity in the …
We review results obtained from vortex-Nernst experiments in cuprates. Evidence for a loss of phase coherence at the Meissner transition $T_{c0}$ is derived from vortex-like excitations that persist to high temperature. Below $T_{c0}$, the…
In hole-doped cuprates, Nernst experiments imply that the superconducting state is destroyed by spontaneous creation of vortices which destroy phase coherence. Using torque magnetometry on $\rm Bi_2Sr_2CaCu_2O_{8+\delta}$, we uncover a…
The observation of a large Nernst signal $e_N$ in an extended region above the critical temperature $T_c$ in hole-doped cuprates provides evidence that vortex excitations survive above $T_c$. The results support the scenario that…
Measurements of the Nernst signal in the vortex-liquid state of the cuprates to high fields (33 T) reveal that vorticity extends to very high fields even close to the zero-field critical temperature $T_{c0}$. In overdoped $\rm…
We calculate the Nernst effect in the vortex fluid phase, which occurs in the lower-T portion of the pseudogap region of the high Tc cuprate phase diagram. The dynamics is dominated by the flows due to both thermally excited vortices and…
In this brief report an attempt is made for a 'mise-a-point' of the subject of the phase fluctuations of the superconducting order parameter above Tc in cuprates, particularly as they appear in underdoped compounds. Measurements of torque…
Fluctuation effects in underdoped cuprates under high fields are examined by trying to fit theoretical results to resistivity and Nernst data in vortex states. The superconducting (SC) fluctuation in underdoped cuprates includes not only…
In the cuprate superconductors, Nernst and torque magnetization experiments have provided evidence that the disappearance of the Meissner effect at $T_c$ is caused by the loss of long-range phase coherence, rather than the vanishing of the…
We theoretically investigate the effect of magnetic field on the pseudogap phenomena in High-Tc cuprates. The obtained results well explain the experimental results including their doping dependences. In our previous paper (J. Phys. Soc.…
A series of recent experiments on the Nernst effect, upper critical field $H_{c2}$ and enhanced diamagnetic magnetization $M$ by Wang et al (PRB 73, 024510), were interpreted as to provide evidence for the pseudogap scenario which…
We present a comparative study of Nernst effect and resistivity in underdoped samples of Bi$_2$Sr$_2$CuO$_{6+\delta}$ and La$_{2-x}$Sr$_{x}$CuO$_4$. The Nernst effect presents a peak in a region of the H-T diagram where resistivity shows a…
We present a study of Nernst effect in underdoped $La_{2-x}Sr_xCuO_4$ in magnetic fields as high as 28T. At high fields, a sizeable Nernst signal was found to persist in presence of a field-induced non-metallic resistivity. By…
We have studied the influence of disorder induced by electron irradiation on the Nernst effect in optimally and underdoped YBa2Cu3O(7-d) single crystals. The fluctuation regime above T_{c} expands significantly with disorder, indicating…
By using thermal and Lorentz force, the vortex motion is successfully manipulated in the mixed state of underdoped La$_{2 - x}$Sr$_{x}$CuO$_{4}$ single crystals and optimally doped YBa$_{2}$Cu$_{3}$O$_{7 - \delta}$ thin films. A conclusion…
A giant Nernst signal was recently observed for fields near crystallographic directions in (TMTSF)$_2$PF$_6$. Such large Nernst signals are most naturally associated with the motion of pancake vortices. We propose a model in which phase…
In hole-doped high-Tc cuprates, the Nernst coefficient (\nu) as well as the magnetoresistance (\Delta\rho/\rho) increase drastically below the pseudo-gap temperature, T^*. This unexpected result attracts much attention in that it reflects…
We present a review of the vortex-Nernst effect in the 3 cuprate families La_{2-x}Sr_xCuO_4, Bi_2Sr_2CaCu_2O_8, and YBa_2Cu_3O_{y}, and discuss the scenario that the superconducting transition in the hole-doped cuprates corresponds to the…
The advent of high transverse-field muon spin rotation (TF-muSR) has led to recent muSR investigations of the magnetic-field response of cuprates above the superconducting transition temperature T_c. Here the results of such experiments on…
We address those puzzling experiments in underdoped high $T_c$ superconductors which have been associated with normal state "vortices" and show these data can be understood as deriving from preformed pairs with onset temperature $T^* >…
When a superconductor is warmed above its critical temperature $T_c$, long range order is destroyed by fluctuations in the order parameter. These fluctuations can be probed by measurements of conductivity, diamagnetism, and of the Nernst…