Effects of hole doping and chemical pressure on the average superconducting kinetic energy of YBa2Cu3O7-δ single crystals

27th International Conference on Low Temperature Physics

Vieira, V.N.^1 ; Mendonça, A.P.A.^1 ; Dias, F.T.^1 ; Da Silva, D.L.D.^1 ; Pureur, P.^2 ; Schaf, J.^2 ; Hneda, M.L.^2 ; Mesquita, F.^2

Instituto de Fisica e Matemática, Universidade Federal de Pelotas, UFPEL, C.P. 354, Pelotas, RS

96010-900, Brazil^1

Instituto de Fisica, Universidade Federal Do Rio Grande Do sul, UFRGS, C. P. 15051, Porto Alegre, RS

91501-970, Brazil^2

关键词: Chemical pressure effects;    Chemical pressures;    DC magnetization;    Kinetic energy density;    Physical information;    SQUID magnetometers;    Temperature rise;    Virial theorems;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/568/2/022049/pdf
DOI  :  10.1088/1742-6596/568/2/022049

来源: IOP

【 摘 要 】

We reported on MZFC(T) and MFCC(T) reversible dc magnetizations of YBa2Cu3O7-δ, Y0.99Ca0.01Ba2Cu3O7-δand YBa1.75Sra0.25Cu3O7-δsingle crystals with a strong focus on The effects of Ca and Sr doping on The average superconducting kinetic energy density, k(T) of The YBa2Cu3O7-δThe k(T) is used as a relevant tool to provide physical information about The HTSC paring mechanism. The determination of The k(T) from MZFC(T) and MFCC(T) data is supported by virial theorem of superconductivity [k(T) -MB]. The MZFC(T) and MFCC(T) measurements were performed with a SQUID magnetometer to H ≤ 50kOe applied parallel to The c axis of The samples. The results show that The samples present a common k(T) behavior that is characterized by a maximum value for T ≤ Tcthat gradually decreases as The temperature rises towards to The Tc, becoming null to T ≤ Tc. The magnetic field affects smoothly The k(T) data behavior. The k(T) results contrasting of our samples shows that The Ca and Sr doping promotes a reduction of its amplitude. A possible explanation to this feature could be associated to The fact that The hole doping character promoted by Ca doping and The chemical pressure effect motivated by Sr doping affects considerably The superconducting paring mechanism of The YBa2Cu3O7-δ.