QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: tigeryzz on August 15, 2009, 05:28

Title: Questions about the Hamiltonian
Post by: tigeryzz on August 15, 2009, 05:28

Hi，
I have try to read the informatuions in the.nc files, but i found that the  dimension of Hamiltonian was hard to understand.
As i know, the Hamiltonian should be a matrix which is formated as N*N.  But the dimentions of Hamiltonian cannot be arranged to a matrix.
So, Why and how should i understand the Hamiltonian in ATK?
Thank you!

Title: Re: Questions about the Hamiltonian
Post by: Nordland on August 15, 2009, 09:05

Hey Tigeryzz.

The hamiltonian is stored in a super sparse format due to the compact nature of the basis set,
and futhermore it is stored in k-independent format.
Therefore it is far from straight forward how to get k-dependent NxN hamiltonian back,
but I will try to cook up a small example for you.

Title: Re: Questions about the Hamiltonian
Post by: tigeryzz on August 15, 2009, 09:46

hi, Nordland,
I have awared that the dimension of the Hamiltonion is depend on different basis set
but in my way, all of thouse are unregular.  :o

Title: Re: Questions about the Hamiltonian
Post by: zh on August 15, 2009, 13:11

Please  read "J. Phys.: Condens. Matter 14 (2002) 2745–2779 (http://www.iop.org/EJ/abstract/0953-8984/14/11/302/)" to understand the dimensions of Hamiltonian matrix.