### Abstract

Filling-control metal-insulator transition on the two-dimensional Hubbard model is investigated by using the correlator projection method, which takes into account the momentum dependence of the free energy beyond the dynamical mean-field theory. The phase diagram of metals and Mott insulators is analyzed. Lifshitz transitions occur simultaneously with metal-insulator transitions for large Coulomb repulsion. On the other hand, they are separated each other for smaller Coulomb repulsion, where the phase sandwiched by the Lifshitz and metal-insulator transitions appears to show violation of the Luttinger sum rule. Through the metal-insulator transition, quasiparticles retain nonzero renormalization factor and finite quasi-particle weight on both sides of the transition. This supports that the metal-insulator transition is caused not by the vanishing renormalization factor but by the relative shift of the Fermi level into the Mott gap away from the quasiparticle band, in sharp contrast with the original dynamical mean-field theory. Charge compressibility diverges at the critical end point of the first-order Lifshitz transition at finite temperatures. The origin of the divergence is ascribed to the singular momentum dependence of the quasiparticle dispersion.

Original language | English |
---|---|

Article number | 084702 |

Journal | Journal of the Physical Society of Japan |

Volume | 75 |

Issue number | 8 |

DOIs | |

Publication status | Published - 2006 Aug 1 |

Externally published | Yes |

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### Keywords

- Compressibility divergence
- Filling control
- Hubbard model
- Lifshitz transition
- Metal-insulator transition
- Quasiparticle dispersion

### ASJC Scopus subject areas

- Physics and Astronomy(all)

### Cite this

**Fate of quasiparticle at Mott transition and interplay with Lifshitz transition studied by correlator projection method.** / Hanasaki, Kota; Imada, Masatoshi.

Research output: Contribution to journal › Article

}

TY - JOUR

T1 - Fate of quasiparticle at Mott transition and interplay with Lifshitz transition studied by correlator projection method

AU - Hanasaki, Kota

AU - Imada, Masatoshi

PY - 2006/8/1

Y1 - 2006/8/1

N2 - Filling-control metal-insulator transition on the two-dimensional Hubbard model is investigated by using the correlator projection method, which takes into account the momentum dependence of the free energy beyond the dynamical mean-field theory. The phase diagram of metals and Mott insulators is analyzed. Lifshitz transitions occur simultaneously with metal-insulator transitions for large Coulomb repulsion. On the other hand, they are separated each other for smaller Coulomb repulsion, where the phase sandwiched by the Lifshitz and metal-insulator transitions appears to show violation of the Luttinger sum rule. Through the metal-insulator transition, quasiparticles retain nonzero renormalization factor and finite quasi-particle weight on both sides of the transition. This supports that the metal-insulator transition is caused not by the vanishing renormalization factor but by the relative shift of the Fermi level into the Mott gap away from the quasiparticle band, in sharp contrast with the original dynamical mean-field theory. Charge compressibility diverges at the critical end point of the first-order Lifshitz transition at finite temperatures. The origin of the divergence is ascribed to the singular momentum dependence of the quasiparticle dispersion.

AB - Filling-control metal-insulator transition on the two-dimensional Hubbard model is investigated by using the correlator projection method, which takes into account the momentum dependence of the free energy beyond the dynamical mean-field theory. The phase diagram of metals and Mott insulators is analyzed. Lifshitz transitions occur simultaneously with metal-insulator transitions for large Coulomb repulsion. On the other hand, they are separated each other for smaller Coulomb repulsion, where the phase sandwiched by the Lifshitz and metal-insulator transitions appears to show violation of the Luttinger sum rule. Through the metal-insulator transition, quasiparticles retain nonzero renormalization factor and finite quasi-particle weight on both sides of the transition. This supports that the metal-insulator transition is caused not by the vanishing renormalization factor but by the relative shift of the Fermi level into the Mott gap away from the quasiparticle band, in sharp contrast with the original dynamical mean-field theory. Charge compressibility diverges at the critical end point of the first-order Lifshitz transition at finite temperatures. The origin of the divergence is ascribed to the singular momentum dependence of the quasiparticle dispersion.

KW - Compressibility divergence

KW - Filling control

KW - Hubbard model

KW - Lifshitz transition

KW - Metal-insulator transition

KW - Quasiparticle dispersion

UR - http://www.scopus.com/inward/record.url?scp=33847289843&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33847289843&partnerID=8YFLogxK

U2 - 10.1143/JPSJ.75.084702

DO - 10.1143/JPSJ.75.084702

M3 - Article

AN - SCOPUS:33847289843

VL - 75

JO - Journal of the Physical Society of Japan

JF - Journal of the Physical Society of Japan

SN - 0031-9015

IS - 8

M1 - 084702

ER -