M. Indenbom - Academia.edu (original) (raw)
Papers by M. Indenbom
Physical Review Letters, 1997
In weakly pinning type-II superconductors the vortex lattice can flow coherently under the action... more In weakly pinning type-II superconductors the vortex lattice can flow coherently under the action of a Lorentz force. This type of collective vortex motion in a random potential is manifested by channeling of the vortex flow along preferred paths which are stable in time. We present direct experimental observations of such vortex flow ``channels'' obtained with magnetic decoration experiments on NbSe2 single crystals.
Journal of Superconductivity, 1993
The magnetic flux distribution from a transport superconducting current flowing through an YBa2Cu... more The magnetic flux distribution from a transport superconducting current flowing through an YBa2Cu3O7 (YBCO) thin film bridge is observed using a ferrimagnetic garnet indicator with in-plane magnetic anisotropy. After switching off the current from the maximum value that provides the electrically detected critical regime, the expected remanent flux was not observed. The only place where the irreversible magnetization takes place is a linear defect that crosses the bridge and thus reduces the electrically measured critical current compared with the value that could be reached without macroscopic defects. The observed reversibility of the main part of the sample is explained on the basis of theoretical calculations of the current-induced flux penetration: Perceptible penetration and trapping of the flux might be observed only upon the application of a current higher than approximately half the maximum critical current that could be reached in such a thin film without macroscopic inhomogeneities.
The polarization-optical contrast in reflected light from twins in YBa2Cu3O(7-x) and GdBa2Cu3O(7-... more The polarization-optical contrast in reflected light from twins in YBa2Cu3O(7-x) and GdBa2Cu3O(7-x) single crystals is investigated. The contrast features due to the presence of narrow (thinner than the light wavelength) twin domains are studied with a transmission electron microscope. Phaseshift values are obtained which indicate a strong anisotropy of the optical conductivity with a preferred direction along the CuO chain.
Acta Crystallographica Section A Foundations of Crystallography, 1981
Acta Crystallographica Section A Foundations of Crystallography, 1981
Magnetic relaxation in the Bragg-glass phase of overdoped Bi_2Sr_2CaCu_2O_8 crystals was investig... more Magnetic relaxation in the Bragg-glass phase of overdoped Bi_2Sr_2CaCu_2O_8 crystals was investigated using time-resolved magneto-optical visualisation of the flux distribution. This has permitted us to extract the current-voltage characteristic, which can be well described by a power-law, although fits to a stretched exponential E \sim \exp(- j_{c} / j)^{\mu} with 0.3 < \mu < 0.8 are possible at long times
Springer Series in Materials Science, 1993
Physical review. B, Condensed matter, 1994
Physical review. B, Condensed matter, 1996
In order to establish the test method of mechanical properties of oxide composite superconductors... more In order to establish the test method of mechanical properties of oxide composite superconductors, an international round-robin test (RRT) has been carried out under the programme of VAMAS activity, for which eight research groups participated. The present RRT made the following guideline clear for assessing the mechanical property of Ag/Bi2223 multifilamentary tapes. Owing to the constitution of the brittle superconductive oxide layer embedded in the ductile metal matrix, the stress-percentage extension (R-A) curve shows a three-stage behaviour, that is, the true elastic region is very narrow and is followed by the quasi-elastic region before reaching the macroscopic plastic region. For assessing the elastic constant, it is recommended to look for the maximum slope carefully by enlarging the initial part of the R-A curve. The following three quantities, elastic constant, yield strength and tensile strength, can be reasonably determined with good accuracy by the procedure reported in this paper. The percentage extension after fracture is, however, excluded from the standard procedure, because it scatters to a great extent owing to the nature of the test sample as well as the experimental limitation.
Physical review. B, Condensed matter, 1995
Physical review. B, Condensed matter, 1995
A flux step between regions of magnetic flux of opposite polarities in the remanent state of Bi2S... more A flux step between regions of magnetic flux of opposite polarities in the remanent state of Bi2Sr2CaCu2O8 single crystals is observed by means of a high resolution magneto-optical technique. This step indicates a current string inside the crystal platelet which is similar to the string appearing in the solution of the critical state problem for a cylindrical type-II superconducting wire
Physical review. B, Condensed matter, 1994
ABSTRACT
Physical Review B, 1995
Parallel linear defects which are inclined to the sample surface normal and crossed linear defect... more Parallel linear defects which are inclined to the sample surface normal and crossed linear defects are introduced into DyBa 2 Cu 3 O 7-δ and Bi 2 Sr 2 CaCu 2 O 8+δ single crystals by high-energy heavy-ion irradiation. The dependence of flux penetration on temperature, fluence, and ...
Physical Review B, 1995
The penetration and exit of magnetic flux in type-II superconductors is investigated for the real... more The penetration and exit of magnetic flux in type-II superconductors is investigated for the realistic situation where a transverse magnetic field is applied to a square or rectangular plate or film. In rectangular specimens the pattern of the sheet current and of the density of the perpendicular flux has some common features with the one-dimensional distributions in circular disks or
Physical Review B, 2002
Detailed measurements of the critical current density jc of YBa2Cu3O7-delta films grown by pulsed... more Detailed measurements of the critical current density jc of YBa2Cu3O7-delta films grown by pulsed laser deposition reveal the increase of jc as a function of film thickness. Both this thickness dependence and the field dependence of the critical current are consistently described using a generalization of the theory of strong pinning of Ovchinnikov and Ivlev [Phys. Rev. B 43, 8024
The contrast between twins in reflected polarized light on different faces of orthorhombic single... more The contrast between twins in reflected polarized light on different faces of orthorhombic single crystals of Y1Ba2Cu3O(7-x) was investigated. It is shown that only the light component with polarization along Cu-O chains in the (001) basis plane experiences phase delay during reflection. This finding supports the existence of one-dimensional conductivity in rare-earth cuprates.
Physical Review Letters, 2000
Source: PubMed CITATIONS 8 READS 24 4 authors, including: Some of the authors of this publication... more Source: PubMed CITATIONS 8 READS 24 4 authors, including: Some of the authors of this publication are also working on these related projects: Dossier SFP : les 100 ans de la supraconductivité View project Cornelis Jacominus van der Beek École Polytechnique 221 PUBLICATIONS 3,909 CITATIONS SEE PROFILE Marcin Konczykowski École Polytechnique 360 PUBLICATIONS 7,728 CITATIONS SEE PROFILE All content following this page was uploaded by Cornelis Jacominus van der Beek on 27 January 2017. The user has requested enhancement of the downloaded file.
Physical Review Letters, 1997
In weakly pinning type-II superconductors the vortex lattice can flow coherently under the action... more In weakly pinning type-II superconductors the vortex lattice can flow coherently under the action of a Lorentz force. This type of collective vortex motion in a random potential is manifested by channeling of the vortex flow along preferred paths which are stable in time. We present direct experimental observations of such vortex flow ``channels'' obtained with magnetic decoration experiments on NbSe2 single crystals.
Journal of Superconductivity, 1993
The magnetic flux distribution from a transport superconducting current flowing through an YBa2Cu... more The magnetic flux distribution from a transport superconducting current flowing through an YBa2Cu3O7 (YBCO) thin film bridge is observed using a ferrimagnetic garnet indicator with in-plane magnetic anisotropy. After switching off the current from the maximum value that provides the electrically detected critical regime, the expected remanent flux was not observed. The only place where the irreversible magnetization takes place is a linear defect that crosses the bridge and thus reduces the electrically measured critical current compared with the value that could be reached without macroscopic defects. The observed reversibility of the main part of the sample is explained on the basis of theoretical calculations of the current-induced flux penetration: Perceptible penetration and trapping of the flux might be observed only upon the application of a current higher than approximately half the maximum critical current that could be reached in such a thin film without macroscopic inhomogeneities.
The polarization-optical contrast in reflected light from twins in YBa2Cu3O(7-x) and GdBa2Cu3O(7-... more The polarization-optical contrast in reflected light from twins in YBa2Cu3O(7-x) and GdBa2Cu3O(7-x) single crystals is investigated. The contrast features due to the presence of narrow (thinner than the light wavelength) twin domains are studied with a transmission electron microscope. Phaseshift values are obtained which indicate a strong anisotropy of the optical conductivity with a preferred direction along the CuO chain.
Acta Crystallographica Section A Foundations of Crystallography, 1981
Acta Crystallographica Section A Foundations of Crystallography, 1981
Magnetic relaxation in the Bragg-glass phase of overdoped Bi_2Sr_2CaCu_2O_8 crystals was investig... more Magnetic relaxation in the Bragg-glass phase of overdoped Bi_2Sr_2CaCu_2O_8 crystals was investigated using time-resolved magneto-optical visualisation of the flux distribution. This has permitted us to extract the current-voltage characteristic, which can be well described by a power-law, although fits to a stretched exponential E \sim \exp(- j_{c} / j)^{\mu} with 0.3 < \mu < 0.8 are possible at long times
Springer Series in Materials Science, 1993
Physical review. B, Condensed matter, 1994
Physical review. B, Condensed matter, 1996
In order to establish the test method of mechanical properties of oxide composite superconductors... more In order to establish the test method of mechanical properties of oxide composite superconductors, an international round-robin test (RRT) has been carried out under the programme of VAMAS activity, for which eight research groups participated. The present RRT made the following guideline clear for assessing the mechanical property of Ag/Bi2223 multifilamentary tapes. Owing to the constitution of the brittle superconductive oxide layer embedded in the ductile metal matrix, the stress-percentage extension (R-A) curve shows a three-stage behaviour, that is, the true elastic region is very narrow and is followed by the quasi-elastic region before reaching the macroscopic plastic region. For assessing the elastic constant, it is recommended to look for the maximum slope carefully by enlarging the initial part of the R-A curve. The following three quantities, elastic constant, yield strength and tensile strength, can be reasonably determined with good accuracy by the procedure reported in this paper. The percentage extension after fracture is, however, excluded from the standard procedure, because it scatters to a great extent owing to the nature of the test sample as well as the experimental limitation.
Physical review. B, Condensed matter, 1995
Physical review. B, Condensed matter, 1995
A flux step between regions of magnetic flux of opposite polarities in the remanent state of Bi2S... more A flux step between regions of magnetic flux of opposite polarities in the remanent state of Bi2Sr2CaCu2O8 single crystals is observed by means of a high resolution magneto-optical technique. This step indicates a current string inside the crystal platelet which is similar to the string appearing in the solution of the critical state problem for a cylindrical type-II superconducting wire
Physical review. B, Condensed matter, 1994
ABSTRACT
Physical Review B, 1995
Parallel linear defects which are inclined to the sample surface normal and crossed linear defect... more Parallel linear defects which are inclined to the sample surface normal and crossed linear defects are introduced into DyBa 2 Cu 3 O 7-δ and Bi 2 Sr 2 CaCu 2 O 8+δ single crystals by high-energy heavy-ion irradiation. The dependence of flux penetration on temperature, fluence, and ...
Physical Review B, 1995
The penetration and exit of magnetic flux in type-II superconductors is investigated for the real... more The penetration and exit of magnetic flux in type-II superconductors is investigated for the realistic situation where a transverse magnetic field is applied to a square or rectangular plate or film. In rectangular specimens the pattern of the sheet current and of the density of the perpendicular flux has some common features with the one-dimensional distributions in circular disks or
Physical Review B, 2002
Detailed measurements of the critical current density jc of YBa2Cu3O7-delta films grown by pulsed... more Detailed measurements of the critical current density jc of YBa2Cu3O7-delta films grown by pulsed laser deposition reveal the increase of jc as a function of film thickness. Both this thickness dependence and the field dependence of the critical current are consistently described using a generalization of the theory of strong pinning of Ovchinnikov and Ivlev [Phys. Rev. B 43, 8024
The contrast between twins in reflected polarized light on different faces of orthorhombic single... more The contrast between twins in reflected polarized light on different faces of orthorhombic single crystals of Y1Ba2Cu3O(7-x) was investigated. It is shown that only the light component with polarization along Cu-O chains in the (001) basis plane experiences phase delay during reflection. This finding supports the existence of one-dimensional conductivity in rare-earth cuprates.
Physical Review Letters, 2000
Source: PubMed CITATIONS 8 READS 24 4 authors, including: Some of the authors of this publication... more Source: PubMed CITATIONS 8 READS 24 4 authors, including: Some of the authors of this publication are also working on these related projects: Dossier SFP : les 100 ans de la supraconductivité View project Cornelis Jacominus van der Beek École Polytechnique 221 PUBLICATIONS 3,909 CITATIONS SEE PROFILE Marcin Konczykowski École Polytechnique 360 PUBLICATIONS 7,728 CITATIONS SEE PROFILE All content following this page was uploaded by Cornelis Jacominus van der Beek on 27 January 2017. The user has requested enhancement of the downloaded file.