Please help me with this program as I am not getting the output?

Z=100*10^-6;% gate width
q=1.6*10^-19;% electron charge
tn=1; %electron life time (value not known)
Popt=10; %incident optical power density
alpha1=0.5; %GaAs optical absorption coefficient(value not known)
d1=0.1 %thickness of GaAs layer(value not known)
h=6.6*10^-34; % plancks constant
c=3*10^8;
lambda=3.5;
Eph=h*c/lambda
Vs=2*10^7; %saturated drift velocity of the photo electrons
nsph=tn*Popt*(1-exp(-alpha1*d1)/d1*Eph)%electron concentration
Idsph=Z*q*nsph*Vs*(1-exp(Vd*u-Vd^2)/Vs*L)% drain to source photo current
plot(I,Vd)

[Anuj]

What is the error that you are getting? Also, have you defined all your variables?

[ARTI]

there is no graph sir

[Walter Roberson]

Vd is still undefined.

[ARTI]

sorry vd=5v; but still there is no graph

[Image Analyst]

Just attach your m-file so we can actually run your complete program. Use the paper clip icon.

[ARTI]

Here am attaching the file.

[Image Analyst]

I don't see it. Maybe you attached it in your other thread. Are both threads discussing the same chunk of code? If so, why do you want to maintain two separate discussions on it?

Answer 1

[Walter Roberson]

Undefined variable Vd.

Answer 2

[Paul]

You have completely undefined your variables, lots are missing such as "Vd","u" and "I"

I have updated your code to give final value as an example.

clc
clear all

% Added variables
Ids=0;
u=6800;  % Needs to be put into units
L=1*10^-6;% gate width
Vd=5;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Z=100*10^-6;% gate width
q=1.6*10^-19;% electron charge
tn=1; %electron life time (value not known)
Popt=10; %incident optical power density
alpha1=0.5; %GaAs optical absorption coefficient(value not known)
d1=0.1; %thickness of GaAs layer(value not known)
h=6.6*10^-34; % plancks constant
c=3*10^8;
lambda=3.5;
Eph=h*c/lambda;
Vs=2*10^7; %saturated drift velocity of the photo electrons
nsph=tn*Popt*(1-exp(-alpha1*d1)/d1*Eph)%electron concentration;
Idsph=Z*q*nsph*Vs*(1-exp(Vd*u-Vd^2)/Vs*L)% drain to source photo current;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
I=Idsph+Ids;
plot(I,Vd)

But not only that your equations are wrong I believe, or at least not complete as you seem to be arriving at Infinity answers which usually suggest improper maths.

Finally the Plot function should not be used for singular values and are used for sets of vectors or matrices.