Publications (45)
Pulsed Laser Deposition of epitaxial titanium diboride thin films
V. Ferrando, D. Marre', P. Manfrinetti +3
Epitaxial titanium diboride thin films have been deposited on sapphire substrates by Pulsed Laser Ablation technique. Structural properties of the films have been studied during th…
Point-contact spectroscopy in neutron-irradiated Mg^{11}B_2
D. Daghero, A. Calzolari, G. A. Ummarino +6
We report on recent results of point-contact spectroscopy measurements in Mg^{11}B_2 polycrystals irradiated at different neutron fluences up to 1.4 x 10^{20} cm^{-2}. The point co…
The behavior of grain boundaries in the Fe-based superconductors
J. H. Durrell, C. -B. Eom, A. Gurevich +4
The Fe-based superconductors (FBS) are an important new class of superconducting materials. As with any new superconductor with a high transition temperature and upper critical fie…
Magnetoresistivity in MgB2 as a probe of disorder in p- and s-bands
I. Pallecchi, V. Ferrando, E. Galleani D'Agliano +10
In this paper we present normal state magnetoresistivity data of magnesium diboride epitaxial thin films with different levels of disorder, measured at 42K in magnetic fields up to…
Small anisotropy, weak thermal fluctuations, and high field superconductivity in Co-doped iron pnictide Ba(Fe1-xCox)2As2
A. Yamamoto, J. Jaroszynski, C. Tarantini +10
We performed high-field magnetotransport and magnetization measurements on a single crystal of the 122-phase iron pnictide Ba(Fe1-xCox)2As2. Unlike the HTS cuprates and 1111-phase…
Enhanced flux pinning in neutron irradiated MgB2
I. Pallecchi, C. Tarantini, H. U. Aebersold +11
We study the effect of neutron irradiation on the critical current density Jc of isotopically pure polycrystalline Mg11B2 samples. For fluences in the range 1017-1018 cm-2, Jc is e…
Evidence for two distinct scales of current flow in polycrystalline Sm and Nd iron oxypnictides
A. Yamamoto, A. A. Polyanskii, J. Jiang +13
Early studies have found quasi-reversible magnetization curves in polycrystalline bulk rare-earth iron oxypnictides that suggest either wide-spread obstacles to intergranular curre…
Significant enhancement of compositional and superconducting homogeneity in Ti rather than Ta-doped Nb3Sn
C. Tarantini, Z. H. Sung, P. J. Lee +2
Nb3Sn wires are now very close to their final optimization but despite its classical nature, detailed understanding of the role of Ta and Ti doping in the A15 is not fully understo…
Artificial and self-assembled pinning centers in Ba(Fe1-xCox)2As2 thin films as a route to very high current density
C. Tarantini, S. Lee, F. Kametani +7
We report on the superior vortex pinning of single and multilayer Ba(Fe1-xCox)2As2 thin films with self-assembled c-axis and artificially introduced ab-plane pins. Ba(Fe1-xCox)2As2…
Effect of two bands on critical fields in MgB2 thin films with various resistivity values
V. Ferrando, P. Manfrinetti, D. Marre' +4
Upper critical fields of four MgB2 thin films were measured up to 28 Tesla at Grenoble High Magnetic Field Laboratory. The films were grown by Pulsed Laser Deposition and showed cr…
Selective mass enhancement close to the quantum critical point in BaFe(AsP)
V. Grinenko, K. Iida, F. Kurth +16
A quantum critical point (QCP) is currently being conjectured for the BaFe(AsP) system at the critical value 0.3. In the proximity of a QCP,…
Development of very high Jc in Ba(Fe1-xCox)2As2 thin films grown on CaF2
C. Tarantini, F. Kametani, S. Lee +6
Ba(Fe1-xCox)2As2 is the most tunable of the Fe-based superconductors (FBS) in terms of acceptance of high densities of self-assembled and artificially introduced pinning centres wh…
Unusually high critical current of clean P-doped BaFe2As2 single crystalline thin film
F. Kurth, C. Tarantini, V. Grinenko +12
Microstructura lly clean, isov alently P-doped BaFe2As2 (Ba-122) single crystalline thin films have been prepared on MgO (001) substrates by molecular beam epitaxy. These films sho…
Strong vortex pinning in Co-doped BaFe2As2 single crystal thin films
C. Tarantini, S. Lee, Y. Zhang +13
We report measurements of the field and angular dependences of Jc of truly epitaxial Co-doped BaFe2As2 thin films grown on SrTiO3/(La,Sr)(Al,Ta)O3 with different SrTiO3 template th…
Systematic study of disorder induced by neutron irradiation in MgB2 thin films
V. Ferrando, I. Pallecchi, C. Tarantini +10
The effects of neutron irradiation on normal state and superconducting properties of epitaxial magnesium diboride thin films are studied up to fluences of 1020 cm-2. All the proper…
Neutron Irradiation of Mg11B2 : From the Enhancement to the Suppression of Superconducting Properties
M. Putti, V. Braccini, C. Ferdeghini +9
In this letter we present the effect of neutron irradiation up to fluences of 3.9 1019 n/cm2 on the superconducting properties of MgB2. In order to obtain a disorder structure homo…
Anomalous hysteresis as an evidence for a magnetic field-induced chiral superconducting state in LiFeAs
G. Li, R. R. Urbano, P. Goswami +6
Magnetometry measurements in high quality LiFeAs single-crystals reveal a change in the sign of the magnetic hysteresis in the vicinity of the upper critical field , from a…
Observation of the Crossover from Two-Gap to Single-Gap Superconductivity through Specific Heat Measurements in Neutron Irradiated MgB2
M. Putti, M. Affronte, C. Ferdeghini +2
We report specific heat measurements in neutron irradiated MgB2 samples, for which the critical temperature has been suppressed down to 8.5 K, but the superconducting transition re…
Anisotropy of the irreversibility field for Zr-doped thin films up to 45T
C. Tarantini, J. Jaroszynski, F. Kametani +6
The anisotropic irreversibility field B of two thin films doped with additional rare earth (RE)=(Gd,Y) and Zr and containing strong correlated pins (spla…
Microwave surface resistance of pristine and neutron-irradiated MgB2 samples in magnetic field
M. Bonura, A. Agliolo Gallitto, M. Li Vigni +2
We report on the microwave surface resistance of two polycrystalline Mg11B2 samples; one consists of pristine material, the other has been irradiated at very high neutron fluence.…
Examination of the tradeoff between intrinsic and extrinsic properties in the optimization of a modern internal tin Nb3Sn conductor
C. Tarantini, P. J. Lee, N. Craig +2
In modern Nb3Sn wires there is a fundamental compromise to be made between optimizing the intrinsic properties associated with the superfluid density in the A15 phase (e.g. Tc, Hc,…
Epitaxial MgB2 thin films on ZrB2 buffer layers: structural characterization by synchrotron radiation
V. Ferrando, C. Tarantini, E. Bellingeri +7
Structural and superconducting properties of magnesium diboride thin films grown by pulsed laser deposition on zirconium diboride buffer layers were studied. We demonstrate that th…
Effect of the four-sheet Fermi surface on magnetoresistivity of MgB2
I. Pallecchi, M. Monni, C. Ferdeghini +4
Recent experimental data of anisotropic magnetoresistivity measured in MgB2 films have shown an intriguing behaviour: the angular dependence of magnetoresistivity changes dramatica…
Fe-based high field superconductors for cost-effective future accelerator magnets
F. Kametani, C. Tarantini, E. Hellstrom
We propose a targeted attack on making the Fe-based superconductor (FBS) AEFe2As2 (122) (AE = alkaline earth, here Ba or Sr) into a much cheaper, higher stability margin, round, tw…
Suppression of the critical temperature of superconducting NdFeAs(OF) single crystals by Kondo-like defect sites induced by alpha-particle irradiation
C. Tarantini, M. Putti, A. Gurevich +8
We report a comprehensive investigation of the suppression of the critical temperature Tc of NdFeAs(OF) single crystal by alpha-particle irradiation. Our data indicate that irradia…
Upper Critical Fields up to 60T in Dirty Magnesium Diboride Thin Films
C. Ferdeghini, V. Ferrando, C. Tarantini +11
Upper critical fields of several magnesium diboride thin films were measured up to 28 T at the Grenoble High Magnetic Field Laboratory (GHMFL) in Grenoble and up to 60 T at the Lab…
Intrinsic and extrinsic pinning in NdFeAs(O,F): vortex trapping and lock-in by the layered structure
C. Tarantini, K. Iida, J. Haenisch +10
The Fe-based superconductors (FBS) present a large variety of compounds whose properties are affected to different extents by their crystal structures. Amongst them, the F…
Effects of neutron irradiation on polycrystalline Mg11B2
C. Tarantini, H. U. Aebersold, V. Braccini +13
We studied the influence of the disorder introduced in polycrystalline MgB2 samples by neutron irradiation. To circumvent self shielding effects due to the strong interaction betwe…
Critical Field of Al-Doped MgB2 Samples: Correlation with the Suppression of Sigma-Band Gap
M. Putti, C. Ferdeghini, M. Monni +7
In this Letter, the study of the effect of Al substitution on the upper critical field, Bc2, in AlxMg1-xB2 samples is presented. We find a straightforward correlation between Bc2 a…
Upper critical fields of MgB2 thin films
V. Ferrando, C. Bernini, P. Manfrinetti +4
Critical fields of four MgB2 thin films with a normal state resistivity ranging from 5 to 50 mWcm and Tc from 29.5 to 38.8 K were measured up to 28 T. Hc2(T) curves present a linea…
Artificially engineered superlattices of pnictide superconductor
S. Lee, C. Tarantini, P. Gao +9
Significant progress has been achieved in fabricating high quality bulk and thinfilm iron-based superconductors. In particular, artificial layered pnictide superlattices offer the…
Multi-band conductivity and multi-gap superconductivity in V3Si from optical measurements on films at terahertz frequencies
A. Perucchi, D. Nicoletti, M. Ortolani +13
The possibility of multi-band conductivity and multi-gap superconductivity is explored in oriented V3Si thin films by means of reflectance and transmittance measurements at teraher…
Probing the electron-phonon coupling in MgB2 through magnetoresistance measurements in neutron irradiated thin films
M. Monni, I. Pallecchi, C. Ferdeghini +9
We report magnetoresistance (MR) measurements on MgB2 and the corresponding full account from ab-initio calculations; we suggest that this combination can be a useful tool to probe…
Evidence for electromagnetic granularity in the polycrystalline iron-based superconductor LaO0.89F0.11FeAs
A. Yamamoto, J. Jiang, C. Tarantini +13
The new rare-earth arsenate superconductors are layered, low carrier density compounds with many similarities to the high-Tc cuprates. An important question is whether they also ex…
Effect of -particle irradiation on a NdFeAs(O,F) thin film
C. Tarantini, K. Iida, N. Sumiya +6
The effect of -particle irradiation on a NdFeAs(O,F) thin film has been investigated to determine how the introduction of defects affects basic superconducting properties, incl…
A Strategic Approach to Advance Magnet Technology for Next Generation Colliders
G. Ambrosio, K. Amm, M. Anerella +74
Colliders are built on a foundation of superconducting magnet technology that provides strong dipole magnets to maintain the beam orbit and strong focusing magnets to enable the ex…
Template engineering of Co-doped BaFe2As2 single-crystal thin films
S. Lee, J. Jiang, C. T. Nelson +14
Understanding new superconductors requires high-quality epitaxial thin films to explore intrinsic electromagnetic properties, control grain boundaries and strain effects, and evalu…
Can antiferromagnetism and superconductivity coexist in the high-field paramagnetic superconductor Nd(O,F)FeAs?
C. Tarantini, A. Gurevich, D. C. Larbalestier +4
We present measurements of the temperature and field dependencies of the magnetization M(T,H) of Nd(O0.89F0.11)FeAs at fields up to 33T, which show that superconductivity with the…
High-field superconductivity in alloyed MgB2 thin films
V. Braccini, A. Gurevich, J. E. Giencke +24
We investigated the effect of alloying on the upper critical field in 12 films, in which disorder was introduced by growth, carbon doping or He-ion irradiation, fi…
Weak-link behavior of grain boundaries in superconducting Ba(Fe1-xCox)2As2 bicrystals
S. Lee, J. Jiang, J. D. Weiss +17
We show that despite the low anisotropy, strong vortex pinning and high irreversibility field Hirr close to the upper critical field Hc2 of Ba(Fe1-xCox)2As2, the critical current d…
High critical fields in MgB2 thin films with various resistivity values
V. Ferrando, C. Tarantini, P. Manfrinetti +4
In this paper, we analyze the upper critical field of four MgB2 thin films, with different resistivity (between 5 to 50 mWcm) and critical temperature (between 29.5 to 38.8 K), mea…
Magnetic ordering of the RE lattice in REFeAsO: the odd case of Sm. A specific heat investigation in high magnetic field
S. Riggs, C. Tarantini, J. Jaroszynski +5
We have investigated the evolution of the low temperature specific heat anomaly (TN=5.4K in zero field) in polycrystalline SmFeAsO samples with magnetic fields up to 35T. The anoma…
Significant enhancement of upper critical fields by doping and strain in Fe-based superconductors
C. Tarantini, A. Gurevich, J. Jaroszynski +7
We report measurements of Hc2(T) up to 85 Tesla on Ba1-xKxAs2Fe2 single crystals and FeSe1-xTex films tuned by doping and strain. We observed an Hc2 enhancement by nearly 25 T at 3…
Magnetic characterization of undoped and 15%F doped LaFeAsO and SmFeAsO compounds
M. R. Cimberle, F. Canepa, M. Ferretti +6
In this paper the magnetic behaviour of undoped and 15% F doped SmFeAsO (Sm-1111) and LaFeAsO (La-1111) samples is presented and discussed. Magnetization measurements are not a sim…
High intergrain critical current density in fine-grain (Ba0.6K0.4)Fe2As2 wires and bulks
J. D. Weiss, C. Tarantini, J. Jiang +4
The K- and Co-doped BaFe2As2 (Ba-122) superconducting compounds are potentially useful for applications because they have upper critical fields (Hc2) of well over 50 T, Hc2 anisotr…