Abstract
A new non-perturbative framework for many-body correlated systems is formulated by extending the operator projection method (OPM). This method offers a systematic expansion which enables us to project into the low-energy structure after extracting the higher-energy hierarchy. This method also opens a way to systematically take into account the effects of collective excitations. The Mott-Hubbard metal-insulator transition in the Hubbard model is studied by means of this projection beyond the second order by taking into account magnetic and charge fluctuations in the presence of the high-energy Mott-Hubbard structure. At half filling, the Mott-Hubbard gap is correctly reproduced between the separated two bands. Near half filling, strongly renormalized low-energy single-particle excitations coexisting with the Mott-Hubbard bands are shown to appear. The significance of the momentum-dependent self-energy in the results is stressed.
| Original language | English |
|---|---|
| Pages (from-to) | 632-635 |
| Number of pages | 4 |
| Journal | Journal of the Physical Society of Japan |
| Volume | 70 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2001 Mar 1 |
| Externally published | Yes |
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Keywords
- Hubbard model
- Metal-insulator transition
- Projection operator
ASJC Scopus subject areas
- Physics and Astronomy(all)
Cite this
Operator Projection Method Applied to the Single-Particle Green's Function in the Hubbard Model. / Onoda, Shigeki; Imada, Masatoshi.
In: Journal of the Physical Society of Japan, Vol. 70, No. 3, 01.03.2001, p. 632-635.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Operator Projection Method Applied to the Single-Particle Green's Function in the Hubbard Model
AU - Onoda, Shigeki
AU - Imada, Masatoshi
PY - 2001/3/1
Y1 - 2001/3/1
N2 - A new non-perturbative framework for many-body correlated systems is formulated by extending the operator projection method (OPM). This method offers a systematic expansion which enables us to project into the low-energy structure after extracting the higher-energy hierarchy. This method also opens a way to systematically take into account the effects of collective excitations. The Mott-Hubbard metal-insulator transition in the Hubbard model is studied by means of this projection beyond the second order by taking into account magnetic and charge fluctuations in the presence of the high-energy Mott-Hubbard structure. At half filling, the Mott-Hubbard gap is correctly reproduced between the separated two bands. Near half filling, strongly renormalized low-energy single-particle excitations coexisting with the Mott-Hubbard bands are shown to appear. The significance of the momentum-dependent self-energy in the results is stressed.
AB - A new non-perturbative framework for many-body correlated systems is formulated by extending the operator projection method (OPM). This method offers a systematic expansion which enables us to project into the low-energy structure after extracting the higher-energy hierarchy. This method also opens a way to systematically take into account the effects of collective excitations. The Mott-Hubbard metal-insulator transition in the Hubbard model is studied by means of this projection beyond the second order by taking into account magnetic and charge fluctuations in the presence of the high-energy Mott-Hubbard structure. At half filling, the Mott-Hubbard gap is correctly reproduced between the separated two bands. Near half filling, strongly renormalized low-energy single-particle excitations coexisting with the Mott-Hubbard bands are shown to appear. The significance of the momentum-dependent self-energy in the results is stressed.
KW - Hubbard model
KW - Metal-insulator transition
KW - Projection operator
UR - http://www.scopus.com/inward/record.url?scp=0035595442&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035595442&partnerID=8YFLogxK
U2 - 10.1143/JPSJ.70.632
DO - 10.1143/JPSJ.70.632
M3 - Article
AN - SCOPUS:0035595442
VL - 70
SP - 632
EP - 635
JO - Journal of the Physical Society of Japan
JF - Journal of the Physical Society of Japan
SN - 0031-9015
IS - 3
ER -