Anomalous thermal conductivity of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">La</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn><mml:mo>−</mml:mo><mml:mi>x</mml:mi></mml:mrow></mml:msub></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">Sr</mml:mi></mml:mrow><mml:mrow><mml:mi>x</mml:mi></mml:mrow></mml:msub></mml:mrow><mml:mi mathvariant="normal">Cu</mml:mi><mml:mrow><mml:msub><mml:mrow><mml:mi mathva

Regueiro, Manuel; Castello, D.; Izbizky, M.A.; Esparza, D.A.; D'Ovidio, C.

doi:10.1103/physrevb.36.8813

Cited by 37 publications

(9 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One immediately notes a substantially higher thermal conductivity for this crystalline medium as compared to the sintered version of the material (the dashed line represents the data of [49]). Moreover, the temperature dependence is very dramatic with a large peak near 40 K and a minimum at higher temperatures that depends on the orientation of the crystal.…”

Section: La2_xsrxcuomentioning

confidence: 90%

“…The process of sintering results in a material that is less than 100% dense. As I have already noted, the voids in such samples effect the thermal conductivity in two ways: they scatter phonons, and reduce [49], x = 0; 9 Bernasconi et aL [64], x = 0. The estimated maximum electronic thermal conductivity for the sample of [62] is indicated by a broken line.…”

Section: La2_xsrxcuomentioning

confidence: 93%

“…Possible tunneling entities suggested include oxygen, oxygen vacancies, and even atomic disorder in the twin domains. Indeed, the T~-temperature dependence of the thermal conductivity [48] of single crystalline YBa2Cu307-~ below 1 K and sintered La2_xSrxCuO4 in the 1-10 K range [49] was viewed as an indication of the presence of two-level tunneling systems. While it is far from certain that this is the only possible interpretation of the data, the question of the existence of tunneling states in the high-T~ superconductors is, perhaps, worth considering.…”

Section: Tunneling States and Thermal Conductivitymentioning

confidence: 99%

“…The question then arises: what is the mechanism by which phonons are scattered within the grains? Regueiro et al [49] argued that the thermal properties of La2_xSrxCuO4 superconductors essentially reflect an amorphous system with two-level tunneling states (TS), and they proposed the existence of a polaronic glass where the key ingredient is oxygen vacancies. According to these authors, the disorder originates from oxygen vacancies and associated polarons that are responsible for a constant mean-free path at high temperatures, while the randomness in vacancy distribution gives rise to the tunneling states that scatter phonons at low temperatures.…”

Section: La2_xsrxcuomentioning

confidence: 99%

See 3 more Smart Citations

Thermal conductivity of high-T c superconductors

Uher

1990

J Supercond

163

View full text Add to dashboard Cite

This paper reviews existing data on the thermal conductivity of high-T c superconductors. Included are discussions of pristine polycrystalline high-Tc ceramics, single crystal specimens, and high-Tc materials structurally modified by substitution or by radiation damage. The thermal conductivity of high-Tc superconductors is compared with that of conventional superconductors, and dramatic differences are found between the two families. Mechanisms of thermal conductivity applicable to high-Tc perovskites are discussed and implications for theories of high-T~ superconductivity are noted.

show abstract

Section: La2_xsrxcuomentioning

confidence: 90%

Section: La2_xsrxcuomentioning

confidence: 93%

Section: Tunneling States and Thermal Conductivitymentioning

confidence: 99%

Section: La2_xsrxcuomentioning

confidence: 99%

See 2 more Smart Citations

Thermal conductivity of high-T c superconductors

Uher

1990

J Supercond

163

View full text Add to dashboard Cite

show abstract

“…In the past, a number of authors claimed that TS exist in cuprate superconductors based mainly on their experimental observations of the glass-like behavior of the thermal conductivity at low temperatures. For example, Regueiro et al [59] measured the in-plane thermal Table 5 Best-fit parameters for the adopted phonon scattering models to express temperature dependence of out-of-plane thermal conductivity of 1000 nm thick YBCO…”

Section: Tunneling States Scatteringmentioning

confidence: 99%

Measurement of Out-of-Plane Thermal Conductivity of Epitaxial $$\hbox {YBa}_{2}\hbox {Cu}_{3}\hbox {O}_{7-{\delta }}$$ Thin Films in the Temperature Range from 10 K to 300 K by Photothermal Reflectance

et al. 2017

View full text Add to dashboard Cite

We measured the out-of-plane (c-axis) thermal conductivity of epitaxially grown YBa 2 Cu 3 O 7−δ (YBCO) thin films (250 nm, 500 nm and 1000 nm) in the temperature range from 10 K to 300 K using the photothermal reflectance technique. The technique enables us to determine the thermal conductivity perpendicular to a thin film on a substrate by curve fitting analysis of the phase lag between the thermoreflectance signal and modulated heating laser beam in the frequency range from 10 2 Hz to 10 6 Hz. The uncertainties of measured thermal conductivity of all samples were estimated to be within ±9 % at 300 K, ±12 % at 180 K, ±16 % at 90 K and ±20 % below 50 K. The experimental results show that the thermal conductivity is dependent on the thickness of the thin films across the entire temperature range. We also observed that the thermal conductivity of the present YBCO thin films showed T 1.4 to T 1.6 glass-like dependence below 50 K, even though the films are crystalline solids. In order to explain the reason for this temperature dependence, we attempted to analyze our results using phonon relaxation times for possible phonon scattering models, including stacking faults, grain boundary and tunneling states scattering models.

show abstract

Evidence of Phase Transition in La1.85CuO4+Δ by Thermal Conductivity

Mucha¹,

Jeżwski²

1990

phys. stat. sol. (a)

View full text Add to dashboard Cite

Anomalous thermal conductivity ofLa2−xSrxCu

Cited by 37 publications

References 17 publications

Thermal conductivity of high-T c superconductors

Thermal conductivity of high-T c superconductors

Measurement of Out-of-Plane Thermal Conductivity of Epitaxial $$\hbox {YBa}_{2}\hbox {Cu}_{3}\hbox {O}_{7-{\delta }}$$ Thin Films in the Temperature Range from 10 K to 300 K by Photothermal Reflectance

Evidence of Phase Transition in La1.85CuO4+Δ by Thermal Conductivity

Contact Info

Product

Resources

About