相关论文: Josephson vortex dynamic in superconducting $YBa_2…
By means of small magnetic field ac susceptibility measurement at 10 kHz we found that the real and imaginary parts of ceramic $YBa_2Cu_3O_ x$ susceptibility in presence of the external low frequency field close to 0.1 Hz exhibit frequency…
We measured the Josephson vortex flow resistance as a function of magnetic field applied parallel to the ab-planes using annealed Y1Ba2Cu3Ox intrinsic Josephson junctions having high anisotropy (around 40) by oxygen content reduction.…
To study the Josephson-vortex system in the intrinsic Josephson junctions, we have measured the flow resistance as a function of magnetic field parallel to the $ab$ plane in Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+y}$ single crystals. Although it…
The properties of a locally frozen (in a region of diameter 0.5 mm) magnetic field in a YBa2Cu3O7-x slab 0.5 mm thick are investigated as a function of the value of the excitation field, the regime of freezing, and the transport current…
Josephson plasma excitations in the high $T_c$ superconductor Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ have been investigated in a wide microwave frequency region (9.8 -- 75 GHz), in particular, in magnetic field applied parallel to the $ab$…
We have investigated the Josephson plasma excitations in magnetic fields parallel to the $ab$-plane in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ single crystals in a wide microwave frequency region (9.8 -- 75 GHz). It was found that there are two…
The Josephson plasma resonance has been investigated in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ single crystals in parallel magnetic fields to the $ab$-plane. We found two resonance modes; one appears at higher frequency in high fields above the…
A cavity perturbation technique is used to study the microwave response of the organic superconductor k-(BEDT-TTF)2Cu(NCS)2. Observation of a Josephson plasma resonance, below Tc (approx. 10 K), enables investigation of the vortex structure…
We study the dynamics of Josephson junction arrays with positional disorder and driven by an external current. We consider weak magnetic fields, corresponding to a frustration $f=n+1/25$ with $n$ integer. We find that above the critical…
In long Josephson junctions with multiple discontinuities of the Josephson phase, fractional vortex molecules are spontaneously formed. At each discontinuity point a fractional Josephson vortex carrying a magnetic flux $|\Phi|<\Phi_0$,…
We propose a phenomenological model that accounts for the history effects observed in ac susceptibility measurements in YBa2Cu3O7 single crystals [Phys. Rev. Lett. 84, 4200 (2000) and Phys. Rev. Lett. 86, 504 (2001)]. Central to the model…
The dynamical vortex response of a two-dimensional array of the resistively shunted Josephson junctions in a perpendicular magnetic field is inferred from simulations. It is found that, as the magnetic field is increased at a fixed…
Vortex matter phases and phase transitions are investigated by means of Josephson plasma resonance in under-doped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ single crystals in a microwave frequency range between 19 and 70 GHz. Accompanied by the…
We investigate dynamics of Josephson vortex lattice in layered high T$_{c}$ superconductors at high magnetic fields. It is shown that the average electric current depends on the lattice structure and is resonantly enhanced when the…
The flux lines dynamics have been investigated on MgB2 bulk superconductors obtained by reactive liquid infiltration by measuring the ac magnetic susceptibility. The fundamental and third harmonics have been studied as a function of…
Fundamental and higher harmonics of the AC magnetic susceptibility have been measured on a LaO_0.92F_0.08FeAs sample as a function of the temperature, at various amplitudes and frequencies of the AC magnetic field, with a small superimposed…
Vortex thermal fluctuations in heavily underdoped Bi2Sr2CaCu2O8+d (Tc=69.4 K) are studied using Josephson plasma resonance (JPR). From the data in zero magnetic field, we obtain the penetration depth along the c-axis, lambda_{L,c}(0) = 229…
We studied response of the Josephson vortex lattice in layered superconductors to the high-frequency c-axis electric field. We found a simple relation connecting the dynamic dielectric constant with the perturbation of the superconducting…
The dynamic interactions between Josephson and pancake vortices in highly anisotropic superconductors are probed by shaking the former vortices with an ac magnetic field and measuring the second harmonic Hall response of the latter vortices…
Using scanning susceptibility microscopy, we shed new light on the dynamics of individual superconducting vortices and examine the hypotheses of the phenomenological models traditionally used to explain the macroscopic ac electromagnetic…