Mott transition and electronic excitation from a Fermi-liquid-like ground state

If the ground state is like a Fermi liquid, it is widely believed that the Mott transition is characterized by the divergence of the effective mass; the dispersion relation of electronic excitation around the Fermi level becomes flat toward the Mott transition. Here, even if the ground state is assumed to be a Fermi-liquid-like state (Gutzwiller wavefunction), the Mott transition is shown to be better characterized by the disappearance of spectral weight from an electron-addition mode which remains dispersing and exhibits the momentum-shifted magnetic dispersion relation in the small hole-doping limit [1]. This characteristic is illustrated in the one-dimensional, two-dimensional, ladder, and bilayer t-J models using a Monte Carlo method and the single-mode approximation [1]. In addition, this characteristic is confirmed in the one-dimensional symmetric t-J model with inverse-squared interaction, whose ground state is known to be the Gutzwiller wavefunction. The results imply that this characteristic is not so sensitive to ground-state properties and generally appears in the Mott transition [1--3]. References: [1] M. Kohno, Phys. Rev. B 102, 165141 (2020). [2] M. Kohno, Rep. Prog. Phys. 81, 042501 (2018). [3] M. Kohno, Phys. Rev. B 92, 085129 (2015).