Emergent Bloch excitations in Mott matter

Abstract

We develop a unified theoretical picture for excitations in Mott systems, portraying both the heavy quasiparticle excitations and the Hubbard bands as features of an emergent Fermi liquid state formed in an extended Hilbert space, which is non-perturbatively connected to the physical system. This observation sheds light on the fact that even the incoherent excitations in strongly correlated matter often display a well defined Bloch character, with pronounced momentum dispersion. Furthermore, it indicates that the Mott point can be viewed as a topological transition, where the number of distinct dispersing bands displays a sudden change at the critical point. Our results, obtained from an appropriate variational principle, display also remarkable quantitative accuracy. This opens an exciting avenue for fast realistic modeling of strongly correlated materials.

Exciton Mott transition revisited

“…(15) with respect to ψ(Γ, γ) we find the results shown in figure 3. In agreement with [48], the g-GW with N = 3 displays for U ∈ [U c1 , U c2 ] the metal-insulator coexistence found in DMFT. The values of the spinodal points, U c1 /2t 1.85 and U c2 /2t 2.88, are slightly underestimated with respect to DMFT, U c1 /2t 2.39 and U c2 /2t 2.94 [58][59][60][61].…”

“…The main difficulty in this context is finding a variational wavefunction that can faithfully describe a Mott insulator. We shall use here a recent extension [48] of the Gutzwiller wavefunction, which has been named ghost Gutzwiller wavefunction (g-GW) and reads…”

Correlation matrix renormalization theory for correlated-electron materials with application to the crystalline phases of atomic hydrogen

“…Yet from our calculation, we note that the change in the double occupancy and the renormalization factor z is rather smooth, hence the metal to insulator transition appears to be a crossover based on our CMR calculation. It has been shown that the Mott physics such as the inter-site spin correlations and incoherent double excitations may not be well described by Gutzwiller approximation (GA) [37][38][39]. The lack of sharp Mott transition in 1D hydrogen chain shown in Fig.…”

Ground-state properties of the Hubbard model in one and two dimensions from the Gutzwiller conjugate gradient minimization theory

“…There have been efforts to access Hubbard models using the GWF [21][22][23][24][25][26]. On one hand, the GA has been widely applied although it sometimes fails to give an accurate description of the model system [21].…”