132 citations · 385 across the 17 of their papers we have counts for
17 papers
Pinning of spiral fluxons by giant screw dislocations in YBa_2Cu_3O_7 single crystals: Josephson analog of the fishtail effect
S. Sergeenkov, L. Jr. Cichetto, V. A. G. Rivera +4
By using a highly sensitive homemade AC magnetic susceptibility technique, the magnetic flux penetration has been measured in YBa_2Cu_3O_7 single crystals with giant screw dislocat…
Temperature oscillations of magnetization observed in nanofluid ferromagnetic graphite
S. Sergeenkov, N. S. Souza, C. Speglich +5
We report on unusual magnetic properties observed in the nanofluid room-temperature ferromagnetic graphite (with an average particle size of l=10nm). More precisely, the measured m…
Manifestation of finite temperature size effects in nanogranular magnetic graphite
S. Sergeenkov, N. S. Souza, C. Speglich +5
In addition to the double phase transition (with the Curie temperatures T_C=300K and T_{Ct}=144K), a low-temperature anomaly in the dependence of the magnetization is observed in t…
Synthesis, characterization and magnetic properties of room-temperature nanofluid ferromagnetic graphite
N. S. Souza, S. Sergeenkov, C. Speglich +7
We report the chemical synthesis route, structural characterization, and physical properties of nanofluid magnetic graphite (NFMG) obtained from the previously synthesized bulk org…
Unusually strong coherent response from grain-boundary Josephson network in polycrystalline Pr_{x}Y_{1-x}Ba_2Cu_3O_7
V. A. G. Rivera, S. Sergeenkov, C. Stari +4
By applying a highly sensitive homemade AC susceptibility technique to Pr_{x}Y_{1-x}Ba_2Cu_3O_7 polycrystals (with x=0.0, 0.1 and 0.3), we observed very sharp Fraunhofer type low-f…
Elastic properties of polycrystalline YBa_2Cu_3O_7: Evidence for granularity induced martensitic behavior
C. Stari, A. Moreno-Gobbi, A. W. Mombru +4
In this work we present the study of the elastic properties of polycrystalline samples of superconducting YBa_2Cu_3O_7 prepared by the sol-gel method. The quality of all samples wa…