Hole dynamics in a 2D doped quantum antiferromagnet within the non-crossing approximation

Satyaki Kar, Efstratios Manousakis

Satyaki Kar, Efstratios Manousakis

Satyaki Kar

Layered structures of the high Tc superconductors have reinstigated the study of two dimensional (2D) antiferromagnetic spin systems and their charge dynamics for more than a couple of decades now. As a hole moves through such a system it interacts with spin waves and phonons at finite temperature. This book contains systematic derivation of the hole spectral functions in a 2D t-J model and its extensions numerically by first finding the spin waves using linear spin wave approximation and then solving the hole Dyson's equation within the Non-crossing approximation. The role of different parameters and scenario on the hole dynamics in such a system is investigated in detail. Particularly the three main chapters in this book deals with hole dynamics (i) when optical phonons are present in the system at finite temperature, (ii) when small but finite hole density is present in the system and (iii) when periodic antiferromagnetic domain walls are present. This book shows computational results extrapolated to thermodynamic limit and its comparison with the angle-resolved-photo-emission spectra of the high Tc Cuprates in order to understand some aspects of charge flow in such compounds.

Jian‐Xin Li, Chang-De Gong

Spin and hole excitations are investigated in the doped two-dimensional (2D) antiferromagnets described by the t-J model based on the spin-wave approximation. The polarizability of spin excitations is found to be consistent with the marginal-Fermi-liquid hypothesis. As a consequence, the imaginary part of the self-energy for holes scattered by the spin excitations is demonstrated to give a linear dependence in temperature T (for \ensuremath{\omega}T) and in frequency \ensuremath{\omega} (for \ensuremath{\omega}>T).

Annabelle Bohrdt, Fabian Grusdt, Michael Knap +7 more

Anna Kauch, Felix Hörbinger, Kitatani, Motoharu +2 more

We study the Hubbard model on a square lattice, using the dynamical vertex approximation and the parquet approximation. These methods allow us to describe the mutual interference of spin-fluctuations in the particle-hole channel and superconducting fluctuations in the cooperon channel in an unbiased way. For small dopings we find predominant commensurable antiferromagnetic spin- and d-wave superconducting fluctuations; for larger doping incommensurate antiferromagnetic spin fluctuations are concomitant to triplet s-wave superconducting fluctuations.