Combinatorial structures in spin models : a method of operator matrices generation

• Autorzy: Bucikiewicz S. , Florek W.
• Języki publikacji: EN

Abstrakty

EN

Finite spin models, applicable to investigations of mesoscopic rings, give rise to eigenproblems of very large dimensions. Efficient, and as exact as possible, solutions of such eigenproblems are very difficult. A method leading to block diagonalization of Hamiltonian matrix is proposed in this paper. For a given symmetry group of a Heisenberg Hamiltonian commuting with the total spin projection (i.e. with the total magnetization being a good quantum number) appropriate combinatorial and group-theoretical structures (partitions, orbits, stabilizers etc.) are introduced and briefly discussed. Generation of these structures can be performed by means of algorithms being modifications of standard ones. Main ideas are presented in this paper, whereas the actual form of algorithms will be discussed elsewhere.

• Wydawca: Institute of Bioorganic Chemistry Scientific Publishers OWN, Polish Academy of Sciences
• Czasopismo: Computational Methods in Science and Technology
• Rocznik: 2001
• Tom: Vol. 7, nr 1
• Strony: 27--39
• Opis fizyczny: Bibliogr. 13 poz.

Twórcy

autor

Bucikiewicz S.

• Adam Mickiewicz University, Institute of Physics Umultowska 85, 61-614 Poznań, Poland

autor

Florek W.

• Adam Mickiewicz University, Institute of Physics Umultowska 85, 61-614 Poznań, Poland

Bibliografia

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