Zero-point lattice expansion and band gap renormalization: Grüneisen approach versus free energy minimization

Zero-Point Energy and 1D Lattice Structures

Zero-point energy (ZPE) can be thought of as a limitless source of potential energy that exists throughout the universe; in essence, ZPE describes the ground state of a quantum mechanical system that exhibits a fluctuating finite energy due to Heisenberg’s uncertainty principle. Quantum mechanics predicts that all of space must be filled with electromagnetic zero-point fluctuations (also called...

Low-energy electronic excitations and band-gap renormalization in CuO

Claudia Rödl,1,2,3 Kari O. Ruotsalainen,4,5 Francesco Sottile,1,3 Ari-Pekka Honkanen,4 James M. Ablett,5 Jean-Pascal Rueff,5,6 Fausto Sirotti,5 Roberto Verbeni,7 Ali Al-Zein,7,8 Lucia Reining,1,3 and Simo Huotari4 1Laboratoire des Solides Irradiés, École polytechnique, CNRS, CEA, Université Paris-Saclay, 91128 Palaiseau cedex, France 2Institut für Festkörpertheorie und -optik, Friedrich-Schille...

Tutorial VI: Phonons, Lattice Expansion, and Band-gap Renormalizationpdfauthor

Strong renormalization of the electronic band gap due to lattice polarization in the GW formalism.

The self-consistent GW band gaps are known to be significantly overestimated. We show that this overestimation is, to a large extent, due to the neglect of the contribution of the lattice polarization to the screening of the electron-electron interaction. To solve this problem, we derive within the GW formalism a generalized plasmon-pole model that accounts for lattice polarization. The resulti...

A Free Energy Minimization

As submitted to Electronics Letters, except including an appendix giving pseudocode. Abstract An algorithm is derived for inferring a binary vector s given noisy observations of Asmodulo2, where A is a binary matrix. Here, the binary vector is replaced by a vector of probabilities, optimized by free energy minimization. Experiments on the inference of the state of a linear feedback shift regist...