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bd177f215a Adds figures 2021-03-19 09:56:48 -05:00
36a10f224d Adds noise calculation again where'd it go 2021-03-18 20:07:33 -05:00

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@@ -242,6 +242,61 @@ We can look at the Nam conductivity now:
As there is as yet no filtering based on the free energy, this is messy, so the comparison to \cref{fig:osRepro1b} is necessary to see which combinations of $T$ and $n$ are valid.
However, this is still quite numerically unstable, even with the dimensional reduction procedure described above for $n$ and $\corr$.
The information that higher $n$ leads to lower $\sigma$ is expected, and does suggest that the implementation is correct, although still very noisy.
\section{Noise calculation}
For our noise calculation, we assume a material parameterised by a Debye frequency $\debye$ and the interaction parameter $N(0) V$.
Because these aren't necessarily experimentally accessible, I tried to keep their values such that they lead to a physically reasonable $T_c$.
In order to keep $N(0) V$ small and $\debye$ bigger than the other parameters, I chose $N(0)V = 0.25$ and $\debye = \SI{1e13}{\per\s}$.
This leads to $T_{c0} = T_c(\mu = 0) = \SI{1.44e11}{\per\s}$, similar to the values used for the equilibrium Nam case.
\begin{enumerate}
\item Use the Owen Scalapino coupled integral equations \cref{eq:gap,eq:n}, find $\mu$ and $\Delta$ for fixed $n$.
\item Find the expected gap from the approximation in OS, $T_c(n) \approx (1 - 4n) T_{c0}$.
If $T > T_c(n)$, then the calculation is skipped (a more complete handling would use either the Lindhard form or use a Nam expression that's been extended to $\Delta = 0$).
This is necessary because the coupled integral equations are very hard to solve
\item Using the modified Nam equations, calculate the dielectric function and create the approximated interpolation form, similar to the equilibrium case.
\item Calculate the noise as usual.
\end{enumerate}
Some examples of the noise are potrayed below, from \crefrange{fig:smallomeganoise}{fig:largerTnoise}.
\begin{figure}[htp]
\centering
\includegraphics[width=14cm]{constOmega/1}
\caption{$T_1$ vs temperature, for very small omega} \label{fig:smallomeganoise}
\end{figure}
\begin{figure}[htp]
\centering
\includegraphics[width=14cm]{constOmega/10}
\caption{$T_1$ vs temperature, for medium omega} \label{fig:mediumomeganoise}
\end{figure}
\begin{figure}[htp]
\centering
\includegraphics[width=14cm]{constOmega/13}
\caption{$T_1$ vs temperature, for big omega} \label{fig:bigomeganoise}
\end{figure}
\begin{figure}[htp]
\centering
\includegraphics[width=14cm]{constT/64}
\caption{$T_1$ vs frequency, for very small temperature} \label{fig:smallTnoise}
\end{figure}
\begin{figure}[htp]
\centering
\includegraphics[width=14cm]{constT/58}
\caption{$T_1$ vs frequency, for medium temperature} \label{fig:mediumTnoise}
\end{figure}
\begin{figure}[htp]
\centering
\includegraphics[width=14cm]{constT/52}
\caption{$T_1$ vs frequency, for larger temperature} \label{fig:largerTnoise}
\end{figure}
\printbibliography
\end{document}