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Suppression of the spin entropy in layered cobalt oxide Ca3Co4O9+δ by Cu doping
Abstract The effect of Cu doping on the spin entropy of Ca 3 Co 4 O 9+ δ system has been investigated through the measurements of magnetothermopower and magnetic properties. It is found that theExpand
Multiple Mode Torsional Oscillator Studies and Evidence for Supersolidity in Bulk 4He
The discovery by Kim and Chan (KC) of an anomalous decrease in the period of torsional oscillators (TO) containing samples of solid He at temperatures below 0.2 K was initially interpreted as aExpand
Effect of V doping on magnetic and electrical transport properties of La0.8Sr0.2Co1−xVxO3
Abstract The effect of V-doping on the magnetic and electrical transport properties for La 0.8 Sr 0.2 Co 1− x V x O 3 ( x =0.00, 0.02, 0.04, and 0.06) has been investigated through X-ray diffraction,Expand
Search for supersolidity in solid 4He using multiple-mode torsional oscillators
Using multiple-frequency torsional oscillators, an experimental technique is used that enables the distinction between the effects of the shear modulus and those of a possible supersolid state, and separate frequency-dependent period shifts arising from changes in the elastic properties of the solid 4He from Possible supersolid signals, which are expected to be independent of frequency. Expand
Interpreting Torsional Oscillator Measurements: Effect of Shear Modulus and Supersolidity
The torsional oscillator is the chief instrument for investigating supersolidity in solid 4He. These oscillators can be sensitive to the elastic properties of the solid helium, which show anomaliesExpand
In Pursuit of the Elusive Supersolid
The excitement following the initial report of supersolid behavior for 4He embedded in porous Vycor glass has been tempered by the realization that many of the early supersolid observations wereExpand
Anomalous behavior of solid 4He in porous Vycor glass.
  • X. Mi, J. Reppy
  • Materials Science, Medicine
  • Physical review letters
  • 3 April 2012
It is found that the signals observed for the solid display a marked period dependence not seen in the case of the superfluid film, suggesting that the low temperature response of solid (4)He in Vycor is more complex than previously assumed and cannot be thought of as a simple superfluid. Expand
Effects of Eu and Fe co-doping on thermoelectric properties of misfit-layered Ca3Co4O9+δ
Polycrystalline Ca3−xEuxCo4−yFeyO9+δ samples were synthesized by a solid-state reaction method and consolidated by spark plasma sintering. Effects of Eu/Fe dual doping on thermoelectric propertiesExpand
Is Supersolid still out there
Evidence for Supersolidity in Bulk Solid $^4$He
We report low temperature measurements of bulk solid $^4$He in a two-frequency compound torsional oscillator with both annular and open cylinder sample geometries. The oscillators were designed toExpand