Effects of pressure and distortion on superconductivity in Tl2Ba2CaCu2O8+δ. (13th October 2015)

• Record Type: Journal Article
• Authors: Zhang, Jian-Bo; Struzhkin, Viktor V; Yang, Wenge; Mao, Ho-Kwang; Lin, Hai-Qing; Ma, Yong-Chang; Wang, Nan-Lin; Chen, Xiao-Jia
• Is Part Of: Journal of physics. Volume 27:Number 44(2015)
• Publication Date: 2015-10-13
• Subjects: pressure -- superconductivity -- distortion -- Raman -- x-ray diffraction; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/0953-8984/27/44/445701
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: The systematic evolution of the structural, vibrational, and superconducting properties of nearly optimally doped Tl2 Ba2 CaCu2 O8+ δ with pressure up to 30 GPa is studied by x-ray diffraction, Raman scattering, and magnetic susceptibility measurements. No phase transformation is observed in the studied pressure regime. The obtained lattice parameters and unit-cell volume continuously decrease with pressure by following the expected equation of state. The axial ratio of c / a exhibits an anomaly starting from 9 GPa. At such a pressure level, the deviation from the nonlinear variation of the phonon frequencies is detected. Both the above observations indicate the enhancement of the distortion upon compression. The superconducting transition temperature is found to exhibit a parabolic behavior with a maximum of 114 K around 7 GPa. We demonstrate that the interplay between the intrinsic pressure variables and distortion controls the superconductivity.