| The density matrix renormalization group(DMRG) is a very powerful numerical tool to study 1D quantum many body systems. In my talk, I would like to focus on some fundamental aspects of DMRG particularly of the infinite system size method, which may be a challenging problem to understand the success of DMRG and its implication to the critical phenomena. When considering the theoretical background of DMRG, it is essentially important to analyze the nature of the eigenvalue spectrum of the reduced density matrix. I explain the relation between the reduced density matrix and the corner Hamiltonian, which is a generator of Baxter's corner transfer matrix in 2D classical systems. I then present a novel real-space-renormalization group approach for this corner Hamiltonian and demonstrate it for the S=1/2 XXZ spin chain. I also examine the renormalization group for the S=1 Heisenberg spin chain and then discuss implications of the eigenvalue spectrum of the corner Hamiltonian to DMRG. |
|
|
|
