11 papers
Magnon-induced hybridization brightens excitons in ferromagnetic semiconductors
Man-Yat Chu, Mona Berciu
Excitons in magnetic semiconductors have energies and spin structures that are sensitive to the underlying magnetic order. We study this coupling in a minimal one-dimensional latti…
Universal thermal breakdown of polaron coherence in one, two, and three dimensions
Jeet Shannigrahi, Janez Bonča, Mona Berciu
How a polaron loses its quasiparticle coherence with increasing temperature is a long-standing open problem. Holstein addressed it in 1959 only in the extreme antiadiabatic, strong…
Finite-temperature Green's function cluster expansion from thermofield doubles: Breakdown of the polaron picture
M. R. Carbone, S. Fomichev, B. Kloss +4
We introduce a method, numerically exact in principle, for computing the momentum- and frequency-resolved single-particle Green's function of a polaron at finite temperature. The m…
Efficient calculation of real-space lattice propagators in the presence of a Fermi sea
Oliver Tong, Mona Berciu
We present an efficient method for computing the real-space propagators (lattice Green's functions) of any tight-binding Hamiltonian in the presence of a Fermi sea with carrier con…
Phonon spectral functions of low-density polaron metals
Luis Walther, Alberto Nocera, Mona Berciu
We use the density matrix renormalization group (DMRG) to compute the phonon spectral function of a one-dimensional spinless Holstein model doped with a low but finite carrier conc…
Hallmark Signatures of Electronic Pairing in Two-Photon Two-Electron Coincidence Angle-Resolved Photoemission Spectroscopy
Janez Bonca, Alberto Nocera, Andrea Damascelli +1
Understanding strongly correlated quantum materials remains a central challenge in condensed matter physics and materials science. While angle-resolved photoemission spectroscopy (…
Fingerprints of preformed pairs in two-electron angle-resolved photoemission spectroscopy
Janez Bonča, Andrea Damascelli, Mona Berciu
We use variational exact diagonalization (VED) to calculate the two-electron removal spectral weight for the Hubbard-Holstein model, starting from the ground-state with two electro…
Advantage of Warm Starts for Electron-Phonon Systems on Quantum Computers
Arnab Adhikary, S. E. Skelton, Alberto Nocera +1
Simulating electron-phonon interactions on quantum computers remains challenging, with most algorithmic effort focused on Hamiltonian simulation and circuit optimization. In this w…
Extended Hubbard Model realized in 2D clusters of molecular anions
Oliver Tong, Katherine A. Cochrane, Bingkai Yuan +3
The Hubbard model, despite its simplicity, is remarkably successful at describing numerous many-body phenomena. However, due to the small class of problems which can be solved exac…
Sharp transitions in the spectra of small Frenkel-like excitons for multi-orbital lattice systems
Man-Yat Chu, Mona Berciu
We propose a method for calculating exciton spectra and wavefunctions for model lattice Hamiltonians, based on real-space electron-hole propagators. We verify that our results agre…
Angle-resolved photoemission intensity for multi-orbital bands: Complex interplay between the self-energy matrix and the optical matrix elements
Yau Chuen Yam, Mona Berciu, George A. Sawayzky
We use a simple one-dimensional two-band model with electron-phonon coupling to illustrate some of the complications that arise in multi-band systems when trying to extract a self-…