|   | 
Details
   web
Records
Author Sereni, J.G.; Huber, J.G.; Luengo, C.A.; Maple, M.B.
Title Calorimetric study of the magnetization of Ce impurities in superconducting Th-Y and Th-Sc alloys Type Journal Article
Year 1978 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 30 Issue 5-6 Pages (down) 729-737
Keywords
Abstract Specific heat measurements are reported in detail for the Ce impurity in the superconducting matrix systems Th65Sc35Ce, Th80Y20Ce, and Th65Y35Ce. The variation of the specific heat jump DeltaC at the superconducting transition temperature T c is indicative of the magnetic nature of an impurity. For Th65Y35Ce a departure is found from the BCS law of corresponding states predicted for a nonmagnetic impurity. This departure is correlated with that observed for (La, Th)Ce systems and related to DeltaT c/n (initial slope of T c vs. n) and Ce effective size (implied by lattice parameter data).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291 ISBN Medium
Area Expedition Conference
Notes ISI:A1978EW47300012 Approved no
Call Number BT @ hernan @ Serial 140
Permanent link to this record
 

 
Author Konstantinov, D.; Homsi, W.; Luzuriaga, J.; Su, C.-K.; Weilert, M.A.; Maris, H.J.
Title How Does a Bubble Chamber Work? Type Journal Article
Year 1998 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 113 Issue 3-4 Pages (down) 485-490
Keywords Bubbles (in fluids); Charged particles; Helium; Hydrogen; Mathematical models; Vapor pressure; Bubble chamber; Saturated vapor pressure; Superfluid helium
Abstract A charged particle passing through a bubble chamber produces a track of bubbles. The way in which these bubbles are produced has been a matter of some controversy. We consider the possibility that in helium and hydrogen bubble chambers the production of bubbles is primarily a mechanical process, rather than a thermal process as has often been assumed. The model we propose gives results which are in excellent agreement with experiment.
Address CNEA, Centro Atomico, (8400) Bariloche, Argentina
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 00222291 (ISSN) ISBN Medium
Area Expedition Conference
Notes Cited By (since 1996): 6; Export Date: 28 April 2009; Source: Scopus; CODEN: JLTPA; Language of Original Document: English; Correspondence Address: Konstantinov, D.; Department of Physics; Brown University Providence, RI 02912, United States; References: Glaser, D.A., (1952) Phys. Rev., 87, p. 665; Glaser, D.A., (1953) Phys. Rev., 91, p. 762; Glaser, D.A., (1954) Nuovo Cimento, 11, p. 361; Seitz, F., (1958) Phys. Fluids, 1, p. 2; Tenner, A.G., (1962) Nucl. Inst. and Meths., 22, p. 1; Rosenblit, M., Jortner, J., (1995) Phys. Rev. Lett., 75, p. 4079; Classen, J., Su, C.-K., Mohazzab, M., Maris, H.J., (1998) Phys. Rev. B, 57, p. 3000; Akulichev, V.A., (1986) Ultrasonics, 24, p. 8; Aleksandrov, Y.A., (1968) Bubble Chambers, , Indiana, Bloomington Approved no
Call Number BT @ luzuriag @ Serial 480
Permanent link to this record
 

 
Author Zemma, E.; Tsubota, M.; Luzuriaga, J.
Title Possible visualization of a superfluid vortex loop attached to an oscillating Beam Type Journal Article
Year 2015 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 179 Issue 5 Pages (down) 310-319
Keywords Quantum fluids; Superfluid helium; Flow visualization; Vortex loops
Abstract Visualization using tracer particles is a relatively new tool available for the study of superfluid turbulence and flow, which is applied here to oscillating objects submerged in the liquid. We report observations of a structure seen in videos taken from outside a cryostat filled with superfluid helium at 2 K, which is possibly a vortex loop attached to an oscillator. The feature, which has the shape of an incomplete arch, is visualized due to the presence of solid H2 tracer particles and is attached to a beam oscillating at 38 Hz in the liquid. It has been recorded in videos taken at 240 frames per second, fast enough to take ∼6 images per period. This makes it possible to follow the structure, and to see that it is not rigid. It moves with respect to the oscillator, and its displacement is in phase with the velocity of the moving beam. Analyzing the motion, we come to the conclusion that we may be observing a superfluid vortex attached to the beam and decorated by the hydrogen particles. An alternative model, considering a solid hydrogen filament, has also been analyzed, but the observed phase between the movement of the beam and the filamentary structure is better explained by the superfluid vortex hypothesis.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number BT @ pedrazp @ Serial 734
Permanent link to this record
 

 
Author Luzuriaga, J.
Title Measurements in the laminar and turbulent regime of superfluid4He by means of an oscillating sphere Type Journal Article
Year 1997 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 108 Issue 3-4 Pages (down) 267-277
Keywords Calculations; Laminar flow; Oscillations; Spheres; Turbulence; Turbulent flow; Vibrations (mechanical); Oscillating sphere; Translational oscillation; Superfluid helium
Abstract The translational oscillations of a sphere in liquid helium have been measured as a way of studying superfluid turbulence. Experiments were carried out in the laminar flow regime for reference purposes, and good agreement found between measured and calculated quantities. In the turbulent region, the dissipation is found to be proportional to the square of the velocity of the sphere, as found previously by other workers. For high vibration amplitudes there is an increase in the hydrodynamic mass. This seems to scale with the superfluid fraction in a way that strongly suggests that the superfluid component plays an important role in the turbulent regime.
Address Comisi
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 00222291 (ISSN) ISBN Medium
Area Expedition Conference
Notes Cited By (since 1996): 2; Export Date: 28 April 2009; Source: Scopus; CODEN: JLTPA; Language of Original Document: English; Correspondence Address: Luzuriaga, J.; Comisi Approved no
Call Number BT @ luzuriag @ Serial 518
Permanent link to this record
 

 
Author Zemma, E.; Luzuriaga, J.
Title Turbulent Flow Around an Oscillating Body in Superfluid Helium: Dissipation Characteristics of the Nonlinear Regime Type Journal Article
Year 2013 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 172 Issue 3-4 Pages (down) 256-265
Keywords Quantum fluids; Turbulence; Superfluid helium; Nonlinear oscillator; Vibrating paddle; Critical velocity
Abstract By examining the resonance curves of an oscillator submerged in superfluid liquid helium, it is found that their shape is affected by two distinct dissipation regimes when the amplitude is large enough to generate turbulence in the liquid. In a resonance curve, the central part close to resonance, may be in a turbulent regime, but the response is of much lower amplitude away from the resonance frequency, so that the oscillation can still be in the linear regime for frequencies not exactly at resonance. This introduces an ambiguity in estimating the inverse quality factor Q −1 of the oscillator. By analyzing experimental data we consider a way of matching the two ways of estimating Q −1 and use the information to evaluate the frictional force as a function of velocity in a silicon paddle oscillator generating turbulence in the superfluid.
Address
Corporate Author Thesis
Publisher Springer US Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number BT @ pedrazp @ Serial 662
Permanent link to this record
 

 
Author Sereni, J.G.
Title Peculiar thermal features of Ce-systems around their critical points Type Journal Article
Year 2007 Publication JOURNAL OF LOW TEMPERATURE PHYSICS Abbreviated Journal
Volume 147 Issue 3-4 Pages (down) 179-197
Keywords
Abstract Some non-predicted thermal behavior observed in various Ce-lattice compounds close to their critical points are presented. From a comparison between phase diagrams driven by doping (x) and pressure, a pre-critical region (x* < x < x(cr)) is identified in the former group. Some systematic behaviors, observed in the specific heat (C-m/T) and the entropy gain, are recognized as characteristic features of that region. Different measured temperature dependencies of C-m/T are compared, detecting that the onset of the non-Fermi-liquid behavior occurs much closer to x* than x(cr). In a detailed analysis of the evolution of the thermal dependence within the pre-critical region, a further change in the T dependence is frequently observed before to reach the critical point. A generalized power law function is proposed to compare different systems, which allows to identify a low temperature C-m/T(T) anomaly that only involves about 0.01 x R ln 2 of entropy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291 ISBN Medium
Area Expedition Conference
Notes ISI:000245133000008 Approved no
Call Number BT @ hernan @ Serial 52
Permanent link to this record
 

 
Author Zemma, E.; Luzuriaga, J.
Title Measurements of Turbulence Onset and Dissipation in Superfluid Helium with a Silicon Double Paddle Oscillator Type Journal Article
Year 2012 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 166 Issue 3-4 Pages (down) 171-181
Keywords
Abstract We have studied experimentally the response of a silicon single crystal double paddle oscillator submerged in superfluid helium from the lambda point to 1.55 K. Measuring the resonance frequency and dissipation on three modes of this high Q system allows us to study the dissipation at the onset of turbulence in the flow around the paddle. The critical velocity V c for turbulence onset decreases with temperature. If we use the density of the normal component of the superfluid to obtain a Reynolds number Re associated with V c we find a value which is largely temperature independent. This result is different from the behavior previously found by other authors below 1 K, where the quantized vorticity (extrinsic nucleation) is observed at velocities more than an order of magnitude greater. In our temperature range, we conclude that the transition is governed by the normal fraction acting as a classical fluid. The laminar regime shows a dissipation that is proportional to the viscous drag calculated by well known formulas for an object oscillating in a liquid. We also find a decrease in resonance frequency in the turbulent regime which is clearly observed but hard to reproduce from run to run.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1573-7357 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number BT @ hernan @ Serial 648
Permanent link to this record
 

 
Author Shalóm, D. E.; Pastoriza, H.
Title Experimental Method to Measure Anisotropic Transport in 2D Superconductors Type Journal Article
Year 2004 Publication Journal of Low Temperature Physics Abbreviated Journal
Volume 135 Issue Pages (down) 153-156
Keywords
Abstract A two-coil kinetic inductance technique for measuring anisotropic response in two-dimensional (2D) superconductors is presented. Serpentine-shaped coils are lithographically patterned directly on top of the sample, separated by isolation layers. The drive and receive coils are positioned in a way that enhances signal from longitudinal currents and reduces transversal ones, maximizing the ratio. Anisotropic transport can be directly measured with this technique, even when anisotropy is induced by the transport current.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number BT @ hernan @ shalom04a Serial 43
Permanent link to this record
 

 
Author Guimpel, J.; de la Cruz, M.E.; de la Cruz, F.; Fink, H.J.; Laborde, O.; Villegier, J.C.
Title Size dependence of the Superconducting critical temperature and fields of Nb/Al multilayers Type Journal Article
Year 1986 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 63 Issue 1-2 Pages (down) 151-165
Keywords
Abstract The critical temperatureT cof Nb/Al multilayers decreases as the total sample thicknessd Tis decreased while the thickness of each Nb and Al layer is kept constant. To understand this behavior, models based on the proximity effect and on weak two-dimensional (2D) localization are employed. The latter uses a characteristic length, the thermal diffusion length, in relation tod Tto obtain 2D behavior and leads to a reasonable explanation ofT c(d T). It is also found that the slope atT c(d T) of the critical magnetic field perpendicular to the layers is independent ofd Twhen the Nb and Al layer thicknesses are kept constant. The angular dependence of the critical field is also measured.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291 ISBN Medium
Area Expedition Conference
Notes ISI:A1986C112200008 Approved no
Call Number BT @ hernan @ Serial 193
Permanent link to this record
 

 
Author Pedrazzini, P.; Berisso, M.G.; Trovarelli, O.; Sereni, J.G.; Geibel, C.
Title Evolution of the ground state in the ternary system CeT2Si2 (T=Cu, Rh and Pd) Type Journal Article
Year 2004 Publication Journal of Low Temperature Physics Abbreviated Journal J. Low Temp. Phys.
Volume 135 Issue 1-2 Pages (down) 143-146
Keywords
Abstract The heavy fermion compounds CeCu2Si2, CeRh2Si2 and CePd2Si2 have been intensively investigated due to the non-conventional relation between superconductivity and magnetism. We have studied these compounds as constituents of a ternary system, where the Ce(RhxCu1-x)(2)Si-2, Ce(PdyRh1-y)(2)Si-2 and Ce(CuzPd1-z)(2)Si-2 alloys span the sides of a triangle with the respective stoichometric compounds at each vertex. In this article we discuss the evolution of the ground state throughout this ternary system, and we analyse (by means of the electrical resistivity) the influence of doping-induced disorder on the Kondo and magnetic ordering temperatures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291 ISBN Medium
Area Expedition Conference
Notes ISI:000189139000019 Approved no
Call Number BT @ hernan @ Serial 66
Permanent link to this record