Recent content by anahita

Thank you very much. Your answer was useful.

I was reading about concept of effective mass on Wikipedia and came across the line that effective mass of a particle can be negative , zero and even infinite. How is this possible?

What is effective mass? What is zero and infinite effective mass?

Hi. Why Zigzag graphene nanoribbons is metallics??

Thanks. But how to calculate second derivative graph x on r?

Hi. How do you calculate Total eigenvalues smaller than a certain value in Matlab?

I have a set of data as follows, How can I calculate the second derivative of the curve obtained from these data. x=[0.1;0.07;0.05;0.03;0]; r=[-98.9407;-105.7183;-111.2423;-116.0320;-120.0462];

I'm using tight binding model. I wants to plotting band structure silicene in path : Γ→M→K→Γ. lattice vectors: a1=a/2*[sqrt(3),-1,0] a2=a/2*[sqrt(3),1,0] silicon atoms are positions at (0,0,0) and (a/sqrt(3),0,0.45).

I want to plot band structure silicene in the following path: Γ→M→K→Γ Do the following equation for the above path is correct: close all clear all clc aa=2.28; a=3.86; a1=(a/2)*[sqrt(3),-1,0]; a2=(a/2)*[sqrt(3),1,0]; b1y=-(2*pi)/a; b1x=(2*pi)/(sqrt(3)*a); b2x=b1x; b2y=-b1y; %K-point pKx =...

The unit cell contains 2N0 carbon atoms which leads to a 2N0x2N0 integral matrix H. matrices developed for the unit cell based on the first nearest neighbour assumption.

What is meant by the following statement? " I can not realize which bases you have taken into account for your Tight Binding calculation" I have used nearest neighbour approximation.

The program is written using the tight binding model.

I want to calculate structure graphene nanoribbons under strain, but the density of states thinks is wrong.

Hi I have plot band structure zigzag graphene nanoribbons with Matlab. I do not know if it is properly written program anyone can help Bug fixes. NU=10; % Number of atoms Nbnd=4*NU; % number of bands aa=2.26; a=sqrt(3)*aa; Csoc=0.0; X(1)=0; Y(1)=0; for ixy=2:NU if mod(ixy,4)==2...

Hi In MATLAB program, cosine directions (n,l,m) not true because inner product R and vectors is impossible. I can't construction matrix Hamiltonian because txy txz , etc are 1*3 vectors while tss is 1*1 vector. can help me?