Сибирский федеральный университет

Тип публикации: статья из журнала

Год издания: 2023

Идентификатор DOI: 10.3390/ma16134640

Аннотация: <jats:p>The physics of high-Tc superconducting cuprates is obscured by the effect of strong electronic correlations. One way to overcome this problem is to seek an exact solution at least within a small cluster and expand it to the whole crystal. Such an approach is at the heart of cluster perturbation theory (CPT). Here, we developed CPT for the dynamic spin and charge susceptibilities (spin-CPT and charge-CPT), with the correlation effects explicitly taken into account by the exact diagonalization. We applied spin-CPT and charge-CPT to the effective two-band Hubbard model for the cuprates obtained from the three-band Emery model and calculated one- and two-particle correlation functions, namely, a spectral function and spin and charge susceptibilities. The doping dependence of the spin susceptibility was studied within spin-CPT and CPT-RPA, that is, the CPT generalization of the random phase approximation (RPA). In the underdoped region, both our methods resulted in the signatures of the upper branch of the spin excitation dispersion with the lowest excitation energy at the (π,π) wave vector and no presence of low-energy incommensurate excitations. In the high doping region, both methods produced a low energy response at four incommensurate wave vectors in qualitative agreement with the results of the inelastic neutron scattering experiments on overdoped cuprates.</jats:p>

Журнал: Materials

Выпуск журнала: Т.16, №13

Номера страниц: 4640

ISSN журнала: 19961944

Место издания: Basel

• Kuz’min Valerii I. (Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok, 660036 Krasnoyarsk, Russia)
• Nikolaev Sergey V. (Department of Theoretical Physics and Wave Phenomena, Siberian Federal University, Svobodny Prospect 79, 660041 Krasnoyarsk, Russia)
• Korshunov Maxim M. (Department of Theoretical Physics and Wave Phenomena, Siberian Federal University, Svobodny Prospect 79, 660041 Krasnoyarsk, Russia)
• Ovchinnikov Sergey G. (Department of Theoretical Physics and Wave Phenomena, Siberian Federal University, Svobodny Prospect 79, 660041 Krasnoyarsk, Russia)

• Ядро РИНЦ (eLIBRARY.RU)