67 lines
1.5 KiB
Matlab
67 lines
1.5 KiB
Matlab
%% conductivity_calculations.m
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%%
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%% calculate and present 2D sheet conductivty for graphene
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close all; clear all; clc;
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%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%% FLAGS & OPTIONS
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%%%%%%%%%%%%%%%%%%%%%%%%%%%
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DISPLAY_HZ = true;
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MIN_F = 9;
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MAX_F = 15;
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F_TOTAL = 1e2;
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%EXCITATION_TYPE = 'intra';
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EXCITATION_TYPE = 'inter';
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%EXCITATION_TYPE = 'all';
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%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%% CALCULATE
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%%%%%%%%%%%%%%%%%%%%%%%%%%%
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x_vals = logspace(MIN_F, MAX_F, F_TOTAL); % hz
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x_vals = x_vals .* (2*pi); % rads-1
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% CALCULATE SHEET CONDUCTIVITY
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cond = zeros(length(x_vals), 2);
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for x=1:length(x_vals)
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cond(x, :) = sheet_conductivity(x_vals(x), % omega (rads-1)
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fermi_from_carrier_density(2.2e17, ev_to_j(2.8)), % fermi_level (J)
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300, % temp (K)
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0.135e-12); % scatter_lifetime (s-1)
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end
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if DISPLAY_HZ % divide radians back to hertz
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x_vals = x_vals ./ (2*pi);
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end
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%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%% RENDER
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%%%%%%%%%%%%%%%%%%%%%%%%%%%
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figure(1);
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hold on;
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%plot(x_vals, real(cond));
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if EXCITATION_TYPE == 'intra'
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semilogx(x_vals, real(cond(:, 1)));
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semilogx(x_vals, imag(cond(:, 1)));
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elseif EXCITATION_TYPE == 'inter'
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semilogx(x_vals, real(cond(:, 2)));
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semilogx(x_vals, imag(cond(:, 2)));
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else
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semilogx(x_vals, real(sum(cond, 2)));
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semilogx(x_vals, imag(sum(cond, 2)));
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end
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legend('Real', 'Imaginary');
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grid;
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title('2D Sheet Conductivity');
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ylabel('Conductivity (S/m)');
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if DISPLAY_HZ
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xlabel('Frequency (Hz)');
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else
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xlabel('Frequency (rads-1)');
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end
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