plotaciv.m

基于Matlab对约瑟夫森结（Josephson Junction）RCSJ模型的交直流I-V特性及非线性混沌现象进行数值模拟。通过计算机数值模拟得到该模型的非线性微分方程数值解

%
% RCSJ模型的直流I-V特性
%
% ****** Author:J.F.Peng([e-mail]) ******
%
clear all;
clc
tic
global Bc ia w id; 
a=[0.60,1.00];
for i=1:2 
    Bc=a(i);
    w=0.50; 
    ia=0.00;
    v=[];
    for id=-2:0.005:2
        [T,Y]=ode45('Josephson_Junction',[0:0.01:80],[0 0 0]);
        v=[v,mean(Y(:,2))];
    end
    plot_id=(-2:0.005:2);
    plot(v,plot_id,'.b','markersize',4)
    % 将Bc=1.00和Bc=0.60的直流I-V特性曲线画一起，好比较
    hold on
end
plot_id=(-2:0.005:2);
plot(v,plot_id,'.r','markersize',4)
xlabel('Voltage U~<dφ/dt>')
ylabel('Directive Current id')
desc={'Bc=0.60(blue)||1.00(red)',
    'w=0.50, ia=0.00, Ic=1'};
text(-3,1.25,desc)
figure
plot_id=(-2:0.005:2);
plot(v,plot_id,'k.','markersize',4)
xlabel('Voltage U~<dφ/dt>')
ylabel('Directive Current id')
desc={'Bc=1.00, w=0.50, ia=0.00, Ic=1'};
text(-1.75,1.25,desc)
%
% RCSJ模型的交流I-V特性
%
clear all;
clc
global Bc ia w id;
Bc=1.00;
w=1.00; 
ia=2.00;
v=[];
for id=-4:0.005:4
    [T,Y]=ode45('Josephson_Junction',[0:0.01:80],[0 0 0]);
    v=[v,mean(Y(:,2))];
end
plot_id=(-4:0.005:4);
figure
plot(v,plot_id,'k.','markersize',4)
xlabel('Voltage U~<dφ/dt>')
ylabel('Directive Current id')
desc={'Bc=1.00 w=1.00, ia=2.00'};
text(-3,2.5,desc)
toc
t=toc