Fast Dynamics in Glass-Formers: Relation to Fragility and the Kohlrausch Exponent

1996 ◽  
Vol 455 ◽  
Author(s):  
K. L. Ngai ◽  
C. M. Roland
Keyword(s):  
Relaxation Time ◽  
Low Temperature ◽  
Specific Heat ◽  
Raman Spectra ◽  
Low Temperatures ◽  
Coupling Model ◽  
Boson Peak ◽  
Specific Heat Data ◽  
Low Temperature Specific Heat ◽  
Heat Data

ABSTRACTFrom the Raman spectra and related inferences from low temperature specific heat data, Sokolov and coworkers have established that the ratio of the quasielastic and vibrational contributions at low temperatures (5∼10K) up to Tg correlates well with the degree of fragility and β of the glass-former. As pointed out by Sokolov (see his contribution in this Volume) such a correlation between the fast dynamics and structural a-relaxation at Tg(i.e., m and β) is intriguing, since at and below Tg, the α-relaxation time τα is more than twelve orders of magnitude longer than the quasielastic contribution and the boson peak. We show in this paper how the Coupling Model (CM) may provide an explanation for this correlation.

LOW TEMPERATURE SPECIFIC HEAT OF YBa2Cu3O7

1993 ◽  
Vol 07 (01n03) ◽  
pp. 166-169 ◽  
Author(s):  
R. CASPARY ◽  
P. HELLMANN ◽  
T. WOLF ◽  
F. STEGLICH
Keyword(s):  
Low Temperature ◽  
Magnetic Fields ◽  
Specific Heat ◽  
Spin Glass ◽  
Oxygen Content ◽  
Theoretical Models ◽  
Specific Heat Data ◽  
Field Dependent ◽  
Low Temperature Specific Heat ◽  
Heat Data

We show specific heat data in magnetic fields to B = 8T on new polycrystals with different oxygen content and compare them with earlier results. The analysis reveals a field dependent residual linear term which is discussed within theoretical models of Bulaevskii and for a spin-glass.

Chemical Ways to YBa2Cu3O7−x Superconducting Materials

1988 ◽  
Vol 121 ◽  
Author(s):  
J. C. Bernier ◽  
S. Vilminot ◽  
S. El Hadigui ◽  
C. His ◽  
J. Guille ◽  
...  
Keyword(s):  
Low Temperature ◽  
Specific Heat ◽  
Magnetic Measurements ◽  
The Other ◽  
Superconducting Materials ◽  
Superconducting Properties ◽  
Specific Heat Data ◽  
Oxalate Coprecipitation ◽  
Low Temperature Specific Heat ◽  
Heat Data

ABSTRACTYBa2Cu3O7−x has been synthesized by two chemical ways, one from oxalate coprecipitation, the other one from metalloorganic decomposition. Superconducting properties of the resulting samples have been checked by means of resistivity and magnetic measurements. Low temperature specific heat data allow to propose an explanation to the residual linear term.

scholarly journals Magnetic studies of monoclinic Cu4O(SeO3)3, a copper-oxo-selenite derivative

2020 ◽  
Vol 233 ◽  
pp. 01002
Author(s):  
José F. Malta ◽  
Marta S.C. Henriques ◽  
José A. Paixão ◽  
António P. Gonçalves
Keyword(s):  
Low Temperature ◽  
Specific Heat ◽  
Intermediate Phase ◽  
Magnetic Transition ◽  
Chemical Vapour ◽  
Specific Heat Data ◽  
Magnetic Studies ◽  
Chemical Vapour Transport ◽  
Maximum Value ◽  
Heat Data

Cu4O(SeO3)3 is a copper-oxo-selenite belonging to the CuxO(SeO3)(x–1) family of the topological chiral magnet Cu2OSeO3. We report magnetometry and specific heat data measured in a monoclinic Cu4O(SeO3)3 single crystal grown through a Chemical Vapour Transport (CVT) reaction. Our study shows a typical antiferromagnetic behaviour, with a Néel temperature TN = 58 K, similar to that of the Cu2OSeO3 and an additional transition at 13 K. The effective magnetic moment per Cu atom is 1.84 μB, close to the expected theoretical value for Cu2+. The low-temperature M(H) curves, show a transition starting at Hc1 ~ 400 Oe at 1.8 K shifting to a lower value of ~ 280 Oe at 30 K, likely from a helical into a conical intermediate phase, and a second transition at Hc2 ~ 1 kOe, above which the net moment increases linearly with applied field. The magnetisation moment value in a 90 kOe field is 0.053 μB/Cu at 1.8 K and attains a maximum value of 0.061 μB at 13 K. Low-temperature specific heat measurements confirm the presence of the magnetic transition at 13 K, slightly shifting to lower temperatures under an applied magnetic field.

Low temperature specific heat anomaly with boson peak in isotope-enriched boron carbides B4·3C – B10C

2020 ◽  
Vol 101 ◽  
pp. 106140
Author(s):  
G. Pristáš ◽  
H. Werheit ◽  
S. Gabáni ◽  
S. Shalamberidze ◽  
K. Flachbart
Keyword(s):  
Low Temperature ◽  
Specific Heat ◽  
Boson Peak ◽  
Low Temperature Specific Heat

THE LOW-TEMPERATURE SPECIFIC HEAT OF U(Pt, Pd)3

1993 ◽  
Vol 07 (01n03) ◽  
pp. 14-17
Author(s):  
H. P. VAN DER MEULEN ◽  
J. J. M. FRANSE ◽  
A. DE VISSER
Keyword(s):  
Magnetic Field ◽  
Low Temperature ◽  
Specific Heat ◽  
Applied Magnetic Field ◽  
Low Temperatures ◽  
Single Crystalline ◽  
Normal Part ◽  
Electron Contribution ◽  
Heavy Electron ◽  
Low Temperature Specific Heat

Specific-heat measurements on single-crystalline samples of U ( Pt 1− x Pd x )3 ( x = 0.00, 0.05 and 0.10) reveal anomalously large values for c/T at low temperatures. The data for UPt 3 have previously been analyzed by making use of the enhanced value of the low-temperature Grüneisen parameter. By this analysis, the heavy-electron contribution to the specific heat has been separated from the normal part that is largely due to the phonon term. Taking this latter term to be the same for all three compounds, the heavy-electron contribution has been evaluated for temperatures below 20 K. This contribution is compared with a spin-1/2 Kondo-type of specific heat. The resulting curves for the x = 0.00 and x = 0.10 alloys are very similar and mainly differ in the temperature at which the maximum is found. The effect of an applied magnetic field within the hexagonal plane, however, shifts the maximum to lower temperatures for x = 0.00 whereas for x = 0.10 a shift towards higher temperatures is found.

Low Temperature Specific Heat in Lightly Mn-Substituted Electron-Doped SrTiO3

2017 ◽  
Vol 86 (8) ◽  
pp. 084601 ◽  
Author(s):  
Tetsuji Okuda ◽  
Hiroto Hata ◽  
Takahiro Eto ◽  
Shogo Sobaru ◽  
Ryosuke Oda ◽  
...  
Keyword(s):  
Low Temperature ◽  
Specific Heat ◽  
Low Temperature Specific Heat
Sign in / Sign up

Export Citation Format

Share Document