# A Band structure silicene nanoribbons

1. Jul 7, 2016

### anahita

I've written the following program for drawing the band structure Silicene nanoribbons, but in a zero energy building is a straight line.
Can help me to fixed problem.
% tight binding calculations for zgnr

clear;
clc;
close all;

NU=14; % Number of atoms in unit cell
Nbnd=4*NU; % number of bands
aa=2.28;
a=3.86;

X(1)=1.9745;
Y(1)=0;

xswitch = 0;

for ixy=2:NU
if mod(ixy,2)==1
Y(ixy)=Y(ixy-1)+aa;
else
Y(ixy)=Y(ixy-1)+aa*sind(30);

X(ixy) = xswitch;

if (ixy+1)<=NU
X(ixy+1)=xswitch;
end

if xswitch == 0
xswitch =aa*cosd(30);
else
xswitch = 0;
end
end
end

for iz=1:NU
if mod(iz,2)==1
Z(iz)=0.46152;
else
Z(iz)=0;
end

end

sho=0;
for is=[0,-1,1]
for ks=1:NU
sho=sho+1;
XT(sho)=X(ks)+is*a;
YT(sho)=Y(ks);
ZT(sho)=Z(ks);
Ax(sho)=is*a;
No(sho)=ks;
end
end
figure(1)
plot(XT,YT,'*')
Ax=Ax/a;

for ik=1:101
K(ik)=-pi+(ik-1)*((2*pi)/100);

H=H0(Nbnd);

for is=1:NU
for js=1:sho
dis=sqrt(((XT(is)-XT(js))^2)+((YT(is)-YT(js))^2));
if abs(dis-2.232)<0.1 & abs(No(is)-No(js))>0
l=(XT(is)-XT(js))/dis;
m=(YT(is)-YT(js))/dis;
n=(ZT(is)-ZT(js))/dis;
h=hamiltonian(l,m,n);

H((No(is)-1)*4+1:No(is)*4,(No(js)-1)*4+1:No(js)*4)=H((No(is)-1)*4+1:No(is)*4,(No(js)-1)*4+1:No(js)*4)+h*exp(i*K(ik)*Ax(js));

end
end

end

E(ik,1:Nbnd)=sort(real(eig(H)));

pl(ik)=(ik-1)/100;
end

figure(2)
plot(E)

2. Jul 12, 2016

### Staff: Admin

Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?

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