diff --git a/talk_short/index.tex b/talk_short/index.tex index 7fb67f6..8ff2baf 100644 --- a/talk_short/index.tex +++ b/talk_short/index.tex @@ -151,8 +151,6 @@ \subsection{Motivation} \end{block} \pause{} \begin{itemize}[<+->] - \item won't call this \emph{heat-flow} because it isn't - \emph{the} thermodynamic heat flow \item nevertheless: may be interesting \emph{qualitative} measure for energy flow \end{itemize} @@ -176,6 +174,7 @@ \subsection{Technical Basics} \item \(B_n=∑_{λ} g_λ\nth a_λ\nth\). \end{itemize} \end{frame} + \begin{frame}{What remains of the Bath?} \begin{block}{Bath Correlation Function} \[α(t-s) = \ev{B(t)B(s)} \qty(\overset{T=0}{=} ∑_λ @@ -191,6 +190,7 @@ \subsection{Technical Basics} \end{itemize} \end{block} \end{frame} + % \begin{frame} % \begin{tikzpicture} % \def\xmin{-.9} @@ -215,46 +215,8 @@ \subsection{Technical Basics} % \end{frame} -\begin{frame}{NMQSD (Zero Temperature)} - Open system dynamics formulated as a \emph{stochastic} differential equation: - \begin{equation} - \label{eq:multinmqsd} - ∂_t\ket{ψ_t(\vb{η}^\ast_t)} = -\iu H(t) \ket{ψ_t(\vb{η}^\ast_t)} + - \vb{L}\cdot\vb{η}^\ast_t\ket{ψ_t(\vb{η}^\ast_t)} - ∑_{n=1}^N L_n^†(t)∫_0^t\dd{s}α_n(t-s)\fdv{\ket{ψ_t(\vb{η}^\ast_t)}}{η^\ast_n(s)}, - \end{equation} - with - \begin{equation} - \label{eq:processescorr} - \begin{aligned} - \mathcal{M}(η_n(t)) &=0, & \mathcal{M}(η_n(t)η_m(s)) &= 0, - & \mathcal{M}(η_n(t)η_m(s)^\ast) &= δ_{nm}α_n(t-s), - \end{aligned} - \end{equation} - by projecting on coherent bath states.\footnote{For details see: - \cite{Diosi1998Mar}} - - System state can be recovered by averaging over \(η\) - \begin{equation} - \label{eq:recover_rho} - ρ_{\sys}(t) = \tr_{\bath}\bqty{\ketbra{ψ(t)}} = - \mathcal{M}_{\vb{η}_{t}^\ast}\bqty{\ketbra{ψ_t(\vb{η}_t)}{ψ_t(\vb{η}^\ast_t)}}. -\end{equation} -\end{frame} - \begin{frame}{HOPS} Using \(α_n(τ)=∑_{\mu}^{M_n}G_μ\nth\eu^{-W_μ\nth τ}\) we define - \begin{equation} - \label{eq:dops} - D_μ\nth(t) \equiv ∫_0^t\dd{s}G_μ\nth\eu^{-W_μ\nth (t-s)}\fdv{η^\ast_n(s)} - \end{equation} - and - \( - D^{\underline{\vb{k}}} \equiv - ∏_{n=1}^N∏_{μ=1}^{M_n} - {\sqrt{\frac{\underline{\vb{k}}_{n,μ}!}{\qty(G\nth_μ)^{\underline{\vb{k}}_{n,μ}}}} - \frac{1}{i^{\underline{\vb{k}}_{n,μ}}}}\qty(D_μ\nth)^{\underline{\vb{k}}_{n,μ}}\), - \( - ψ_{t}^{\kmat} \equiv D^\kmatψ_{t}\) we find \begin{multline} \label{eq:multihops} @@ -275,14 +237,6 @@ \section{Bath Observables with HOPS} J = - \dv{\ev{H_\bath}}{t} = \ev{L^†∂_t B(t) + L∂_t B^†(t)}_\inter. \end{equation} \pause{} \ldots some manipulations \ldots{}\pause{} - \begin{block}{Result (NMQSD)} - \begin{equation} - \label{eq:final_flow_nmqsd} - J(t) = -\i \mathcal{M}_{η^\ast}\bra{\psi(η, - t)}L^†\dot{D}_t\ket{\psi(η^\ast,t)} + \cc - \end{equation} - \end{block} - with \(\dot{D}_t = ∫_0^t\dd{s} \dot{\alpha}(t-s)\fdv{η^\ast_s}\).\pause{} \begin{block}{Result (HOPS)} \begin{equation} \label{eq:hopsflowfock} @@ -396,7 +350,7 @@ \subsection{Otto Cycle} \includegraphics{figs/otto/power} \end{figure} \begin{itemize} - \item \(\bar{P} = .0025\), + \item \(\bar{P} = 0.0025\), \(η\approx 29\%\), \(T_{c}=1\), \(T_{h}=20\) \item no tuning of parameters, except for resonant coupling \item long bath memory \(ω_{c}=1\), but weak-ish coupling @@ -809,6 +763,71 @@ \section{Other Projects} \end{itemize} \end{frame} +\begin{frame}{What remains of the Bath?} + \begin{block}{Bath Correlation Function} + \[α(t-s) = \ev{B(t)B(s)} \qty(\overset{T=0}{=} ∑_λ + \abs{g_λ}^2\,\eu^{-\iu ω_λ (t-s)})= \frac{1}{π} ∫J(ω) \eu^{-\iu ω + t}\dd{ω}\] + \end{block} + \pause + \begin{block}{Spectral Density} + \[J(ω) = π ∑_{λ} \abs{g_{λ}}^{2}δ(ω-ω_{λ})\] + \begin{itemize} + \item in thermodynamic limit \(\to\) smooth function + \item here usually: Ohmic SD \(J(ω)=η ω \eu^{-ω/ω_c}\) (think phonons) + \end{itemize} + \end{block} +\end{frame} +\begin{frame}{NMQSD (Zero Temperature)} + Open system dynamics formulated as a \emph{stochastic} differential equation: + \begin{equation} + \label{eq:multinmqsd} + ∂_t\ket{ψ_t(\vb{η}^\ast_t)} = -\iu H(t) \ket{ψ_t(\vb{η}^\ast_t)} + + \vb{L}\cdot\vb{η}^\ast_t\ket{ψ_t(\vb{η}^\ast_t)} - ∑_{n=1}^N L_n^†(t)∫_0^t\dd{s}α_n(t-s)\fdv{\ket{ψ_t(\vb{η}^\ast_t)}}{η^\ast_n(s)}, + \end{equation} + with + \begin{equation} + \label{eq:processescorr} + \begin{aligned} + \mathcal{M}(η_n(t)) &=0, & \mathcal{M}(η_n(t)η_m(s)) &= 0, + & \mathcal{M}(η_n(t)η_m(s)^\ast) &= δ_{nm}α_n(t-s), + \end{aligned} + \end{equation} + by projecting on coherent bath states.\footnote{For details see: + \cite{Diosi1998Mar}} + + System state can be recovered by averaging over \(η\) + \begin{equation} + \label{eq:recover_rho} + ρ_{\sys}(t) = \tr_{\bath}\bqty{\ketbra{ψ(t)}} = + \mathcal{M}_{\vb{η}_{t}^\ast}\bqty{\ketbra{ψ_t(\vb{η}_t)}{ψ_t(\vb{η}^\ast_t)}}. +\end{equation} +\end{frame} +\begin{frame}{HOPS} + Using \(α_n(τ)=∑_{\mu}^{M_n}G_μ\nth\eu^{-W_μ\nth τ}\) we define + \begin{equation} + \label{eq:dops} + D_μ\nth(t) \equiv ∫_0^t\dd{s}G_μ\nth\eu^{-W_μ\nth (t-s)}\fdv{η^\ast_n(s)} + \end{equation} + and + \( + D^{\underline{\vb{k}}} \equiv + ∏_{n=1}^N∏_{μ=1}^{M_n} + {\sqrt{\frac{\underline{\vb{k}}_{n,μ}!}{\qty(G\nth_μ)^{\underline{\vb{k}}_{n,μ}}}} + \frac{1}{i^{\underline{\vb{k}}_{n,μ}}}}\qty(D_μ\nth)^{\underline{\vb{k}}_{n,μ}}\), + \( + ψ_{t}^{\kmat} \equiv D^\kmatψ_{t}\) + we find + \begin{multline} + \label{eq:multihops} + \dot{ψ}_{t}^\kmat = \qty[-\iu H_\sys(t) + \vb{L}(t)\cdot\vb{η}_{t}^\ast - + ∑_{n=1}^N∑_{μ=1}^{M_n}\kmat_{n,μ}W\nth_μ]ψ_{t}^\kmat \\+ + \iu ∑_{n=1}^N∑_{μ=1}^{M_n}\sqrt{G\nth_μ}\qty[\sqrt{\kmat_{n,μ}} L_n(t)ψ_{t}^{\kmat - + \mat{e}_{n,μ}} + \sqrt{\qty(\kmat_{n,μ} + 1)} L^†_n(t)ψ_{t}^{\kmat + + \mat{e}_{n,μ}} ]. + \end{multline} +\end{frame} + \end{document}