From 7a1eeffa42e1f039f4e49fafed40921fd2e2ff19 Mon Sep 17 00:00:00 2001 From: Pierre-Francois Loos Date: Mon, 22 Jun 2020 15:33:51 +0200 Subject: [PATCH] test for Antoine --- Notes/BSEdyn-notes.tex | 92 +++++++++++++++++++++--------------------- 1 file changed, 46 insertions(+), 46 deletions(-) diff --git a/Notes/BSEdyn-notes.tex b/Notes/BSEdyn-notes.tex index c8078a0..1b24ddf 100644 --- a/Notes/BSEdyn-notes.tex +++ b/Notes/BSEdyn-notes.tex @@ -667,53 +667,53 @@ For the double excitation, dBSE2 yields a slightly better energy, yet still in q %%% %%% %%% %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -%\subsection{The forgotten kernel: Sangalli's kernel} -%\label{sec:Sangalli} +\subsection{The forgotten kernel: Sangalli's kernel} +\label{sec:Sangalli} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -%\titou{This section is experimental...} -%In Ref.~\onlinecite{Sangalli_2011}, Sangalli proposed a dynamical kernel (based on the second RPA) without (he claims) spurious excitations thanks to the design of a number-conserving approach which correctly describes particle indistinguishability and Pauli exclusion principle. -%We will first start by writing down explicitly this kernel as it is given in obscure physicist notations in the original article. -% -%The Hamiltonian with Sangalli's kernel is (I think) -%\begin{equation} -% \bH_\text{S}^{\sigma}(\omega) = -% \begin{pmatrix} -% \bR_\text{S}^{\sigma}(\omega) & \bC_\text{S}^{\sigma}(\omega) -% \\ -% -\bC_\text{S}^{\sigma}(-\omega) & -\bR_\text{S}^{\sigma}(-\omega) -% \end{pmatrix} -%\end{equation} -%with -%\begin{subequations} -%\begin{gather} -% R_{ia,jb}^{\sigma}(\omega) = \delta_{ij} \delta_{ab} (\eGW{a} - \eGW{i}) + f_{ia,jb}^{\sigma} (\omega) -% \\ -% C_{ia,jb}^{\sigma}(\omega) = f_{ia,bj}^{\sigma} (\omega) -%\end{gather} -%\end{subequations} -%and -%\begin{subequations} -%\begin{gather} -% f_{ia,jb}^{\sigma} (\omega) = \sum_{m \neq n} \frac{ c_{ia,mn} c_{jb,mn} }{\omega - ( \omega_{m} + \omega_{n})} -% \\ -% c_{ia,mn}^{\sigma} = \frac{1}{2} \sum_{jb,kc} \qty{ \qty[ \ERI{ij}{kc} \delta_{ab} + \ERI{kc}{ab} \delta_{ij} ] \qty[ R_{m,jc} R_{n,kb} -% + R_{m,kb} R_{n,jc} ] } -%\end{gather} -%\end{subequations} -%where $R_{m,ia}$ are the elements of the RPA eigenvectors. -% -%For the two-level model, Sangalli's kernel reads -%\begin{align} -% R(\omega) & = \Delta\eGW{} + f_R (\omega) -% \\ -% C(\omega) & = f_C (\omega) -%\end{align} -% -%\begin{gather} -% f_R (\omega) = 2 \frac{ [\ERI{vv}{vc} + \ERI{vc}{cc}]^2 }{\omega - 2\omega_1} -% \\ -% f_C (\omega) = 0 -%\end{gather} +\titou{This section is experimental...} +In Ref.~\onlinecite{Sangalli_2011}, Sangalli proposed a dynamical kernel (based on the second RPA) without (he claims) spurious excitations thanks to the design of a number-conserving approach which correctly describes particle indistinguishability and Pauli exclusion principle. +We will first start by writing down explicitly this kernel as it is given in obscure physicist notations in the original article. + +The Hamiltonian with Sangalli's kernel is (I think) +\begin{equation} + \bH_\text{S}^{\sigma}(\omega) = + \begin{pmatrix} + \bR_\text{S}^{\sigma}(\omega) & \bC_\text{S}^{\sigma}(\omega) + \\ + -\bC_\text{S}^{\sigma}(-\omega) & -\bR_\text{S}^{\sigma}(-\omega) + \end{pmatrix} +\end{equation} +with +\begin{subequations} +\begin{gather} + R_{ia,jb}^{\sigma}(\omega) = \delta_{ij} \delta_{ab} (\eGW{a} - \eGW{i}) + f_{ia,jb}^{\sigma} (\omega) + \\ + C_{ia,jb}^{\sigma}(\omega) = f_{ia,bj}^{\sigma} (\omega) +\end{gather} +\end{subequations} +and +\begin{subequations} +\begin{gather} + f_{ia,jb}^{\sigma} (\omega) = \sum_{m \neq n} \frac{ c_{ia,mn} c_{jb,mn} }{\omega - ( \omega_{m} + \omega_{n})} + \\ + c_{ia,mn}^{\sigma} = \frac{1}{2} \sum_{jb,kc} \qty{ \qty[ \ERI{ij}{kc} \delta_{ab} + \ERI{kc}{ab} \delta_{ij} ] \qty[ R_{m,jc} R_{n,kb} + + R_{m,kb} R_{n,jc} ] } +\end{gather} +\end{subequations} +where $R_{m,ia}$ are the elements of the RPA eigenvectors. + +For the two-level model, Sangalli's kernel reads +\begin{align} + R(\omega) & = \Delta\eGW{} + f_R (\omega) + \\ + C(\omega) & = f_C (\omega) +\end{align} + +\begin{gather} + f_R (\omega) = 2 \frac{ [\ERI{vv}{vc} + \ERI{vc}{cc}]^2 }{\omega - 2\omega_1} + \\ + f_C (\omega) = 0 +\end{gather} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{Take-home messages}