Nernst, Seebeck, and Hall effects in the mixed state of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">YBa</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Cu</mml:mi></mml:mrow><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math><

Ri, H.-C.; Gross, Rudolf; Gollnik, F.; Beck, A.; Huebener, R. P.; Wagner, Patrick; Adrian, H.

doi:10.1103/physrevb.50.3312

Cited by 135 publications

(115 citation statements)

References 107 publications

Supporting

Mentioning

102

Contrasting

Order By: Relevance

“…But the peak does not shift to lower temperatures as the field is increased. This is in sharp contrast with the behavior observed in optimally-doped cuprates, where the Nernst peak follows the field-induced shift in resistive transition [20]. Note that in both samples at 12T, the peak occurs at a temperature interval where resistivity is increasing with decreasing temperature.…”

contrasting

confidence: 48%

Anomalous dissipation in the mixed state of underdoped cuprates close to the superconductor-insulator boundary

Capan

Behnia

et al. 2003

Phys. Rev. B

View full text Add to dashboard Cite

We present a comparative study of Nernst effect and resistivity in underdoped samples of Bi2Sr2CuO 6+δ and La2−xSrxCuO4. The Nernst effect presents a peak in a region of the H-T diagram where resistivity shows a non-metallic temperature dependence. Our results illustrate that the mechanism of dissipation in the mixed state of underdoped cuprates is poorly understood. Large quantum superconducting fluctuations and vanishing vortex viscosity are among suggested explanations for an enhanced Nernst signal close to the superconductor-insulator boundary.PACS numbers: 72.15. Jf, 74.25.Fy, 74.40.+k, 74.60.Ge Recently, the peculiar behavior of Nernst effect in copper oxide superconductors has become a subject of growing attention [1,2,3,4,5,6,7,8,9]. In conventional superconductors, Nernst effect, namely the transverse component of the thermopower in a magnetic field, is known to be associated with vortex movement [10]. However, Xu et al. [1] reported that in underdoped La 2−x Sr x CuO 4 a large residual signal persists in the normal state and well above T c . This observation has been confirmed in other families of cuprate superconductors including Bi 2 Sr 2 CuO 6+δ and YBa 2 Cu 3 O 6+y [2,3]. The normalstate Nernst signal is present over a wide doping range, but attenuates as one moves towards the superconductorinsulator boundary or the overdoped regime in the phase diagram [2]. Remarkably, the temperature scale up to which such an anomalous Nernst signal extends is about 130K, regardless of the particular system studied. Moreover, the Nernst signal is found to persist at magnetic fields as high as 30T both in overdoped [3] and in underdoped [4] compounds.The debate on the origin of this residual Nernst signal in the normal state of underdoped cuprates is still open and has stimulated a number of theoretical works during the past months. Fluctuations of the superconducting order parameter above T c are considered to be the most plausible explanation for such a signal. Ussishkin, Sondhi and Huse [5], for example, used a TimeDependent-Ginzburg-Landau(TDGL) approach. Within gaussian approximation and subtracting magnetization currents, they found a sizeable Nernst signal due to superconducting fluctuations. Weng and Muthukumar [7] have suggested that in a Resonant-Valence-Bond(RVB) picture, the coupling of spinon vortices to holons, can give rise to an enhanced Nernst effect above T c in the so-called spontaneous vortex phase. A different route has been taken by Kontani[6] who calculated Nernst coefficient beyond the Relaxation Time Approximation. By taking a self-consistent account of vertex corrections for currents, he found that the quasi-particle contribution to Nernst effect is no longer negligible in presence of antiferromagnetic and superconducting fluctuations. These studies point to the presence of strong superconducting fluctuations in the pseudogap regime and suggest that the superconducting transition is not a meanfield transition[11] but rather a vortex-antivortex unbinding type of transition [12]. It is ...

show abstract

contrasting

confidence: 48%

Anomalous dissipation in the mixed state of underdoped cuprates close to the superconductor-insulator boundary

Capan

Behnia

et al. 2003

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…This phenomenon has been extensively studied in the high-T c superconductors, known to exhibit a strong enhancement of N in the vortex-liquid state. 15,67,68 In contrast, no sizable vortex contribution to N has yet been detected in HF systems (see, for example, Ref. 61); that is, the vortices are assumed to be immobile.…”

Section: F Thermoelectric Properties Ii: Nernst Effectmentioning

confidence: 99%

Heavy fermion superconductor CeCu2Si2under high pressure: Multiprobing the valence crossover

Seyfarth

Rüetschi²,

Sengupta³

et al. 2012

Phys. Rev. B

View full text Add to dashboard Cite

The first heavy fermion superconductor CeCu 2 Si 2 has not revealed all its striking mysteries yet. At high pressures, superconductivity is supposed to be mediated by valence fluctuations, in contrast to ambient pressure, where spin fluctuations most likely act as pairing glue. We have carried out a multiprobe (electric transport, thermopower, ac specific heat, Hall and Nernst effects) experiment up to 7 GPa on a high-quality CeCu 2 Si 2 single crystal. For the first time, the resistivity data make it possible quantitatively to draw the valence crossover line within the p-T plane and to locate the critical end point at 4.5 ± 0.2 GPa and a slightly negative temperature. In the same pressure region, remarkable features have also been detected in the other physical properties, presumably acting as further signatures of the Ce valence crossover and the associated critical fluctuations: We observe maxima in the Hall and Nernst effects and a sign change and a strong sensitivity on magnetic field in the thermopower signal.

show abstract

“…However, it should be mentioned that scaling behavior was observed far beyond the possible vortex-glass transition. 21 A phenomenological model, based on an entirely different approach, has been proposed by Vinokur et al, 47 who have calculated the effect of pinning on the Hall resistivity. In their model the Hall conductivity σ xy ∼ = ρ xy /ρ 2 xx (|ρ xy | ≪ ρ xx ) is independent of disorder and the scaling law ρ xy ∼ρ 2 xx is believed to be a general feature of any vortex state with disorder-dominated dynamics.…”

Section: Regimesmentioning

confidence: 99%

Hall effect inLuNi2B2Cand<

et al. 1999

View full text Add to dashboard Cite

The Hall effect in LuNi2B2C and YNi2B2C borocarbides has been investigated in normal and superconducting mixed states. The Hall resistivity ρxy for both compounds is negative in the normal as well as in the mixed state and has no sign reversal below Tc typical for high-Tc superconductors. In the mixed state the behavior of both systems is quite similar. The scaling relation ρxy ∼ ρ β xx (ρxx is the longitudinal resistivity) was found with β = 2.0 and 2.1 for annealed Luand Y-based compounds, respectively. The scaling exponent β decreases with increasing degree of disorder and can be varied by annealing. This is attributed to a variation of the strength of flux pinning. In the normal state weakly temperature dependent Hall coefficients were observed for both compounds. A distinct nonlinearity in the ρxy dependence on field H was found for LuNi2B2C in the normal state below 40 K, accompanied by a large magnetoresistance (MR) reaching +90% for H = 160 kOe at T = 20 K. At the same time for YNi2B2C only linear ρxy(H) dependences were observed in the normal state with an approximately three times lower MR value. This difference in the normal state behavior of the very similar Lu-and Y-based borocarbides seems to be connected with the difference in the topology of the Fermi surface of these compounds.

show abstract

Nernst, Seebeck, and Hall effects in the mixed state ofYBa2Cu3<

Cited by 135 publications

References 107 publications

Anomalous dissipation in the mixed state of underdoped cuprates close to the superconductor-insulator boundary

Anomalous dissipation in the mixed state of underdoped cuprates close to the superconductor-insulator boundary

Heavy fermion superconductor CeCu2Si2under high pressure: Multiprobing the valence crossover

Hall effect inLuNi2B2Cand<

Contact Info

Product

Resources

About