Location-sensitive measurement of the local fluctuation of driven vortex density in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Bi</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Sr</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">CaCu</mml:m

Maeda, Akiko; Tsuboi, Takashi; Abiru, Ryuichi; Togawa, Yoshihiko; Kitano, Haruhisa; Iwaya, Katsuya; Hanaguri, T.

doi:10.1103/physrevb.65.054506

Cited by 24 publications

(17 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The above estimate demonstrates that the correlation length of moving vortices becomes much larger than the static correlation length. Such a long correlation length for moving vortex was also observed in the noise measurement of the bulk single crystal of Bi 2 Sr 2 CaCu 2 O y [24]. To be quantitative, using the collective creep theory, the data in Fig.…”

supporting

confidence: 65%

Static friction as a function of waiting time probed by the dynamics of driven vortices in La_{2 −x}Sr_xCuO₄thin films

Nakamura¹,

Kubo²,

Kitamura³

et al. 2010

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

We systematically investigated the waiting-time dependence of the maximum static friction force, F(s)(t(w)), using the dynamics of driven vortices in a high-T(c) superconductor as a model system. F(s)(t(w)) was measured in La(2 - x)Sr(x)CuO(4) thin films with different structures, sample sizes and pinning force. We found that F(s)(t(w)) by thermal fluctuation is strongly affected by the pinning strength, the vortex bundle size and the system size. Based on these results, we found crucial conditions to determine the validity of the Amontons-Coulomb's law, and proposed a criterion.

show abstract

supporting

confidence: 65%

Static friction as a function of waiting time probed by the dynamics of driven vortices in La_{2 −x}Sr_xCuO₄thin films

Nakamura¹,

Kubo²,

Kitamura³

et al. 2010

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…Noise fluctuations have also been used as another method to study the dynamics of magnetic systems [32]. In superconducting vortex systems, the plastic flow regime is associated with large voltage noise fluctuations of a f 1 form [33][34][35][36], while when the system dynamically orders at higher drives, narrow band noise features appear and the noise power is strongly reduced [26,[37][38][39]. Here we show that changes in the skyrmion Hall angle are correlated with changes in the skyrmion velocity fluctuations and the shape of the velocity noise spectrum.…”

Section: Introductionmentioning

confidence: 99%

Noise fluctuations and drive dependence of the skyrmion Hall effect in disordered systems

2016

View full text Add to dashboard Cite

Using a particle-based simulation model, we show that quenched disorder creates a drive-dependent skyrmion Hall effect as measured by the change in the ratio =R V V of the skyrmion velocity perpendicular (V ⊥ ) and parallel (V ) to an external drive. R is zero at depinning and increases linearly with increasing drive, in agreement with recent experimental observations. At sufficiently high drives where the skyrmions enter a free flow regime, R saturates to the disorder-free limit. This behavior is robust for a wide range of disorder strengths and intrinsic Hall angle values, and occurs whenever plastic flow is present. For systems with small intrinsic Hall angles, we find that the Hall angle increases linearly with external drive, as also observed in experiment. In the weak pinning regime where the skyrmion lattice depins elastically, R is nonlinear and the net direction of the skyrmion lattice motion can rotate as a function of external drive. We show that the changes in the skyrmion Hall effect correlate with changes in the power spectrum of the skyrmion velocity noise fluctuations. The plastic flow regime is associated with f 1 noise, while in the regime in which R has saturated, the noise is white with a weak narrow band signal, and the noise power drops by several orders of magnitude. At low drives, the velocity noise in the perpendicular and parallel directions is of the same order of magnitude, while at intermediate drives the perpendicular noise fluctuations are much larger.

show abstract

“…[11][12][13][14][15] These models have also been applied to interpret the noise generated in crystalline or high textured HTS thin films. [16][17][18] A very different situation exists in the case of disordered granular HTS, both in the case where the grain interface behaves as a weak-link, as in YBCO, 19 or as a rather strong link, as in MgB 2 . 20,21 For these materials the current noise generated in stationary conditions is generally interpreted on the basis of percolation-like models in the presence of temperature fluctuations [22][23][24][25][26] and is, almost invariably, of the 1 / f type.…”

Section: Introductionmentioning

confidence: 99%

Resistive transition process in granular superconductingMgB2films by analysis and simulation of the generated current noise

et al. 2008

View full text Add to dashboard Cite

An original model for the interpretation of the noise produced during the resistive transition of disordered granular MgB 2 superconductive films is presented and tested by comparison with extended experiments on these types of films. Both the amplitude and frequency behavior of the noise power spectrum, simulated on the basis of this model, are in very good agreement with the experimental results, practically without the introduction of adjustable parameters. The model is based on the onset of correlated transitions of large sets of grains, forming resistive layers through the film cross-section area during the transition process. The strong nonlinear behavior and correlation of the grains produces abrupt resistance variations, giving rise to the large noise, of the 1 / f 3 type, observed in experiments. These results show that, even in the case where the grain interface behaves as a strong link, as in MgB 2 , if the grains are randomly oriented and are strongly anisotropic in regard to their critical current density, the transition models based on fluxoids depinning and motion, used for single crystals or grain oriented films, cannot be applied, at least when the transition takes place near the critical temperature at low bias currents. These models would justify a current noise power spectrum 2 or 3 orders of magnitude lower than the observed one in the low frequency range. Since the intrinsic superconductive properties of the material do not enter in its development, it is believed that this model may be generally applicable to disordered granular high-temperature superconductors, at least when the conditions of temperature and bias current specified above are met.

show abstract

Location-sensitive measurement of the local fluctuation of driven vortex density inBi2Sr2CaCu

Cited by 24 publications

References 46 publications

Static friction as a function of waiting time probed by the dynamics of driven vortices in La_{2 −x}Sr_xCuO₄thin films

Static friction as a function of waiting time probed by the dynamics of driven vortices in La_{2 −x}Sr_xCuO₄thin films

Noise fluctuations and drive dependence of the skyrmion Hall effect in disordered systems

Resistive transition process in granular superconductingMgB2films by analysis and simulation of the generated current noise

Contact Info

Product

Resources

About

Location-sensitive measurement of the local fluctuation of driven vortex density inBi2Sr2CaCu

Cited by 24 publications

References 46 publications

Static friction as a function of waiting time probed by the dynamics of driven vortices in La2 −xSrxCuO4thin films

Static friction as a function of waiting time probed by the dynamics of driven vortices in La2 −xSrxCuO4thin films

Noise fluctuations and drive dependence of the skyrmion Hall effect in disordered systems

Resistive transition process in granular superconductingMgB2films by analysis and simulation of the generated current noise

Contact Info

Product

Resources

About

Static friction as a function of waiting time probed by the dynamics of driven vortices in La_{2 −x}Sr_xCuO₄thin films

Static friction as a function of waiting time probed by the dynamics of driven vortices in La_{2 −x}Sr_xCuO₄thin films