55 citations · 206 across the 16 of their papers we have counts for
5 papers · 1 filter
Exploring quantum phase transitions by the cross derivative of the ground state energy
H. Y. Wu, Yu-Chin Tzeng, Z. Y. Xie +2
In this work, the cross derivative of the Gibbs free energy, initially proposed for phase transitions in classical spin models [Phys. Rev. B 101, 165123 (2020)], is extended for qu…
Cross derivative: a universal and efficient method for phase transitions in classical spin models
Y. Chen, K. Ji, Z. Y. Xie +1
With an auxiliary weak external magnetic field, we reexamine the fundamental thermodynamic function, Gibbs free energy F(T, h), to study the phase transitions in the classical spin…
Novel theoretical approach in photoemission spectroscopy: application to isotope effect and boron-doped diamond
Jifeng Yu, Kai Ji, Keiichiro Nasu
A new path-integral theory is developed to calculate the photoemission spectra (PES) of correlated many-electron systems. The application to the study on Bi2Sr2CaCu2O8 (Bi2212) and…
Theoretical study on isotopic shift in angle-resolved photoemission spectra of Bi2Sr2CaCu2O8
Kai Ji, Keiichiro Nasu
We develop a path-integral theory to study the angle-resolved photoemission spectra (ARPES) of high-T_c superconductors based on a two-dimensional model for the CuO2 conduction pla…
Isotopic shift in angle-resolved photoemission spectra of Bi2Sr2CaCu2O8 due to quadratic electron-phonon coupling
Kai Ji, Keiichiro Nasu
In connection with the experiment on oxygen isotope effect of Bi2Sr2CaCu2O8 with the angle-resolved photoemission spectroscopy (ARPES), we theoretically study the isotope-induced b…