Publications (32)
Magnetism and superconductivity in Ru(1-x)Sr2RECu(2+x)O(8-d) (RE=Gd, Eu) and RuSr2Gd(1-y)Ce(y)Cu2O8 compounds
P. W. Klamut, B. Dabrowski, S. M. Mini +13
We discuss the properties of new superconducting compositions of Ru(1-x)Sr2RECu(2+x)O(8-d) (RE=Gd, Eu) ruthenocuprates that were synthesized at 600 atm. of oxygen at 1080 C. By cha…
Specific heat studies of the phase transitions in multiferroic SrBaMnTiO system ()
J. Wieckowski, A. Szewczyk, M. U. Gutowska +1
Specific heat studies of the SrBaMnTiO polycrystalline samples performed by the relaxation and DSC methods over the temperature range 2 - 450 K are repo…
Relaxation Effects in the Transition Temperature of Superconducting HgBa2CuO4+delta
S. Sadewasser, J. S. Schilling, J. L. Wagner +4
In previous studies on a number of under- and overdoped high temperature superconductors, including YBa_{2}Cu_{3}O_{7-y} and Tl_{2}Ba_{2}CuO_{6+δ}, the transition temperature T_c…
Resolving spatial and temporal shock structures using LOFAR observations of type II radio bursts
D. E. Morosan, I. C. Jebaraj, P. Zhang +6
Collisionless shocks are one of the most powerful particle accelerators in the Universe. In the heliosphere, type II solar radio bursts are signatures of electrons accelerated by c…
Strain-mediated metal-insulator transition in epitaxial ultra-thin films of NdNiO3
Jian Liu, M. Kareev, B. Gray +5
We have synthesized epitaxial NdNiO ultra-thin films in a layer-by-layer growth mode under tensile and compressive strain on SrTiO (001) and LaAlO (001), respective…
Absence of room temperature ferromagnetism in bulk Mn-doped ZnO
S. Kolesnik, B. Dabrowski
Structural and magnetic properties have been studied for polycrystalline Zn_1-xMn_xO (x=0.02, 0.03, 0.05). Low-temperature (~500 oC) synthesis leaves unreacted starting ZnO and man…
Source location and evolution of a multi-lane type II radio burst
P. Zucca, P. Zhang, K. Kozarev +8
Shocks in the solar corona can accelerate electrons that in turn generate radio emission known as type II radio bursts. The characteristics and morphology of these radio bursts in…
Superconductivity in Ru(1-x)Sr2GdCu(2+x)O(8-y) Compounds
P. W. Klamut, B. Dabrowski, S. Kolesnik +2
We report on the properties of new ruthenocuprates Ru(1-x)Sr2GdCu(2+x)O(8-y) (x=0, 0.1, 0.2, 0.3, 0.4, 0.75) that extend the superconductivity found previously in RuSr2GdCu2O8 (Tc=…
Magnetic phase diagram of Ca_1-xMn_xO
S. Kolesnik, B. Dabrowski
Alternating current susceptibility and direct current magnetization have been studied for polycrystalline CaMnO. On increasing the Mn content, magnetic ordering changes…
Distinct Magnetic Phases in Structurally Uniform SrCoO
Z. H. Zhu, F. J. Rueckert, J. I. Budnick +7
Two magnetic phase transitions have been noted for SrCoO for near-stoichiometric oxygen concentrations (small y). Using muon spin rotation and neutron scattering experiment…
Negative Refraction in Ferromagnet/Superconductor Superlattices
A. Pimenov, P. P. Przyslupski, B. Dabrowski +1
Negative refraction, which reverses many fundamental aspects of classical optics, can be obtained in systems with negative magnetic permeability and negative dielectric permittivit…
Tuning of magnetic and electronic states by control of oxygen content in lanthanum strontium cobaltites
S. Kolesnik, B. Dabrowski, J. Mais +4
We report on the magnetic, resistive, and structural studies of perovskite LaSrCoO. By using the relation of synthesis temperature and oxygen partial press…
Magnetic phase diagram of cubic perovskites SrMn_1-xFe_xO_3
S. Kolesnik, B. Dabrowski, J. Mais +5
We combine the results of magnetic and transport measurements with Mossbauer spectroscopy and room-temperature diffraction data to construct the magnetic phase diagram of the new f…
Suppression of Magnetic Phase Separation in Epitaxial SrCoOx Films
F. J. Rueckert, Y. F. Nie, C. Abughayada +6
Using pulsed laser deposition and a unique fast quenching method, we have prepared SrCoOx epitaxial films on SiTiO3 substrates. As electrochemical oxidation increases the oxygen co…
Nuclear Magnetic Resonance and Magnetization Studies of the Ferromagnetic Ordering Temperature Suppression in Ru Deficient SrRuO3
Z. H. Han, J. I. Budnick, M. Daniel +7
The synthesis of SrRuO3 under high-pressure oxygen produces a nonstoichiometric form with randomly distributed vacancies on the Ru-sites, along with a significantly reduced ferroma…
An Overview of the 2014 ALMA Long Baseline Campaign
ALMA Partnership, E. B. Fomalont, C. Vlahakis +246
A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to make accurate images with resolutions of tens of milliarcseconds, which at submillimeter (submm) wavel…
^{99,101}Ru NMR and ^{63,65}Cu NQR Study of the Magnetic Superconductors RuSr_{2}EuCu_{2}O_{8} and RuSr_{2}GdCu_{2}O_{8}
Z. H. Han, J. I. Budnick, W. A. Hines +3
In order to investigate the coexistence of magnetism and superconductivity on a microscopic scale, local studies using zero-field spin-echo ^{99,101}Ru NMR and ^{63,65}Cu NQR have…
Driven Vortex States and Relaxation in Single Crystal
V. Metlushko, U. Welp, I. Aranson +5
The vortex response to various ac-drives has been studied in high quality single crystals. Well within the vortex solid phase a re-entrant resistive state has been o…
On the effect of heterovalent substitutions in ruthenocuprates
P. W. Klamut, B. Dabrowski, S. M. Mini +14
We discuss the properties of superconducting derivatives of the RuSr2GdCu2O8 (1212-type) ruthenocuprate, for which heterovalent doping has been achieved through partial substitutio…
Quantum Oscillations in the Underdoped Cuprate YBa2Cu4O8
E. A. Yelland, J. Singleton, C. H. Mielke +4
We report the observation of quantum oscillations in the underdoped cuprate superconductor YBa2Cu4O8 using a tunnel-diode oscillator technique in pulsed magnetic fields up to 85T.…
Local studies of the ferromagnetic ordering temperature suppression in SrRuO3
Z. H. Han, J. I. Budnick, M. Daniel +7
In order to gain insight into suppression of the ferromagnetic ordering temperature, local studies utilizing 99,101Ru zero-field spin-echo NMR, along with complimentary magnetizati…
Structural and magnetic properties of transition metal substituted ZnO
S. Kolesnik, B. Dabrowski, J. Mais
Structural and magnetic properties have been studied for polycrystalline Zn_{1-x}TM_xO, where TM (transition metal ions) = Mn, Fe, and Co. No bulk ferromagnetism was observed for s…
Charge order in SrCoO investigated through resonant soft x-ray scattering
F. J. Rueckert, F. He, B. Poudel +4
Resonant soft X-ray scattering was used to determine the presence of more subtle orderings not detected in standard structural analyses. By tuning to specific Co absorption edges,…
Origin of spin-glass behavior of Zn_1-xMn_xO
S. Kolesnik, B. Dabrowski, J. Mais
ac susceptibility has been studied for polycrystalline ZnMnO. Stoichiometric samples demonstrate Curie-Weiss behavior, which indicates mostly antiferromagnetic interact…
LOFAR observations of the quiet solar corona
C. Vocks, G. Mann, F. Breitling +9
The quiet solar corona emits meter-wave thermal bremsstrahlung. Coronal radio emission can only propagate above that radius, , where the local plasma frequency eqals the obse…
Magnetic Properties of RuSr2RECu2O8 (RE=Gd, Eu) and Ru1-xSr2GdCu2+xO8-y Superconductors
P. W. Klamut, B. Dabrowski, S. M. Mini +11
Synthesis in 1% oxygen at 930C leads to non-superconducting RuSr2GdCu2O8 in which superconductivity subsequently can be induced with oxygen annealings without observable stoichiome…
Structural and physical properties of perovskites
S. Kolesnik, B. Dabrowski, O. Chmaissem
We combine the results of magnetic and transport measurements with neutron diffraction data to construct the structural and magnetic phase diagram of the entire family of SrMn$_{1-…
Increase of critical currents and peak effect in Mo substituted YBaCuO
K. Rogacki, B. Dabrowski, O. Chmaissem
Superconducting critical currents A/cm at temperatures K and magnetic fields T are reported for the YBaCuMoO$_{7+d…
Shock location and CME 3D reconstruction of a solar type II radio burst with LOFAR
P. Zucca, D. E. Morosan, A. P. Rouillard +62
Type II radio bursts are evidence of shocks in the solar atmosphere and inner heliosphere that emit radio waves ranging from sub-meter to kilometer lengths. These shocks may be ass…
Fragile charge order in the non-superconducting ground state of the underdoped high temperature superconductors
B. S. Tan, N. Harrison, Z. Zhu +7
The normal state in the hole underdoped copper oxide superconductors has proven to be a source of mystery for decades. The measurement of a small Fermi surface by quantum oscillati…
Determining the acceleration regions of in situ electrons using remote radio and X-ray observations
D. E. Morosan, N. Dresing, C. Palmroos +13
Solar energetic particles in the heliosphere are produced by flaring processes on the Sun or shocks driven by coronal mass ejections. These particles are regularly detected remotel…
Asymmetric orbital-lattice interactions in ultra-thin correlated oxide films
J. Chakhalian, J. M. Rondinelli, Jian Liu +14
Using resonant X-ray spectroscopies combined with density functional calculations, we find an asymmetric bi-axial strain-induced -orbital response in ultra-thin films of the cor…