clear all; close all; clc; format long; %constantes me = 9.10955*10^(-31); eV = 1.6021895*10^(-19); hb = 1.0545896*10^(-34); mp = 1.672651*10^(-27); a = 1*10^(-10); function [p] = rho(E,m,hb) p = sqrt((2*m*E)/hb^2); endfunction function [k] = kha(E,m,hb,V) k = sqrt((2*m*(E-V))/hb^2); endfunction function [a] = alph(E,m,hb,V) a = sqrt((2*m*(V-E))/hb^2); endfunction %rho(3*eV,me,hb) %kha(3*eV,me,hb,2*eV) %alph(2*eV,me,hb,4*eV) function [r] = Ref(E,m,hb,V,a) if(E == V) p = rho(E,m,hb); r = p*p*a*a/4; r = r/(1+r); else p = rho(E,m,hb); k = kha(E,m,hb,V); r = (p^2-k^2)/(2*p*k); r = r*r; r = (r*(sin(k*a))^2)/(1+r*(sin(k*a))^2); endif endfunction function [t] = Tran(E,m,hb,V,a) if(E == V) p = rho(E,m,hb); t = p*p*a*a/4; t = 1/(1+t); else p = rho(E,m,hb); k = kha(E,m,hb,V); t = (p^2-k^2)/(2*p*k); t = t*t; t = 1/(1+t*(sin(k*a))^2); endif endfunction function [r] = Refc(E,m,hb,V,a) if(E == 0) r = 1; elseif(E == V) p = rho(E,m,hb); r = p*p*a*a/4; r = r/(1+r); else p = rho(E,m,hb); k = alph(E,m,hb,V); r = (p^2-k^2)/(2*p*k); r = r*r; r = (r*(sinh(k*a))^2)/(1+r*(sinh(k*a))^2); endif endfunction function [t] = Tranc(E,m,hb,V,a) if(E == 0) t = 0; elseif(E == V) p = rho(E,m,hb); t = p*p*a*a/4; t = 1/(1+t); else p = rho(E,m,hb); k = alph(E,m,hb,V); t = (p^2-k^2)/(2*p*k); t = t*t; t = 1/(1+t*(sinh(k*a))^2); endif endfunction N = 200; E = linspace(0,5*eV,N); Rc = zeros(N); Tc = zeros(N); for i = 1:N if(E(i) < 2*eV) Rc(i) = Refc(E(i),me,hb,2*eV,a); Tc(i) = Tranc(E(i),me,hb,2*eV,a); else Rc(i) = Ref(E(i),me,hb,2*eV,a); Tc(i) = Tran(E(i),me,hb,2*eV,a); endif endfor Ex = E/eV; l1 = length(Ex); l2 = length(Rc); %coefficients R et T %figure; %plot(Ex,Rc,Ex,Tc) % cas E = 3eV, v0 = 2eV p3 = rho(3*eV,me,hb); k3 = kha(3*eV,me,hb,2*eV); function [aa] = AA(E,m,hb,V,a) p = rho(3*eV,me,hb); k = kha(3*eV,me,hb,2*eV); endfunction