TRIQS: A toolbox for research on interacting quantum systems

Parcollet, Olivier; Ferrero, Michel; Ayral, Thomas; Hafermann, Hartmut; Krivenko, Igor; Messio, Laura; Seth, Priyanka

doi:10.1016/j.cpc.2015.04.023

Cited by 381 publications

(305 citation statements)

References 19 publications

Supporting

Mentioning

291

Contrasting

Order By: Relevance

“…8(b) compares our results with ones we obtained using a continuous-time QMC method to solve the twoorbital impurity problem. For the QMC, we employed a hybridization expansion algorithm in matrix form as implemented in the TRIQS package 17,18,63 . This allows us to perform calculations for the full rotationally-invariant Hamiltonian Eq.…”

Section: Two-band Hubbard Modelmentioning

confidence: 99%

See 1 more Smart Citation

Efficient DMFT impurity solver using real-time dynamics with matrix product states

et al. 2015

View full text Add to dashboard Cite

We propose to calculate spectral functions of quantum impurity models using the Time Evolving Block Decimation (TEBD) for Matrix Product States. The resolution of the spectral function is improved by a so-called linear prediction approach. We apply the method as an impurity solver within the Dynamical Mean Field Theory (DMFT) for the single-and two-band Hubbard model on the Bethe lattice. For the single-band model we observe sharp features at the inner edges of the Hubbard bands. A finite size scaling shows that they remain present in the thermodynamic limit. We analyze the real time-dependence of the double occupation after adding a single electron and observe oscillations at the same energy as the sharp feature in the Hubbard band, indicating a long-lived coherent superposition of states that correspond to the Kondo peak and the side peaks. For a two-band Hubbard model we observe an even richer structure in the Hubbard bands, which cannot be related to a multiplet structure of the impurity, in addition to sharp excitations at the band edges of a type similar to the single-band case.

show abstract

Section: Two-band Hubbard Modelmentioning

confidence: 99%

“…Many different approaches have been proposed to tackle the problem. The most common ones are QMC 8,[15][16][17][18][19] , exact diagonalization (ED) [20][21][22][23] , and NRG [24][25][26] . QMC can efficiently handle multiple bands, but when formulated in imaginary time, it lacks high resolution of the spectral function.…”

Section: Introductionmentioning

confidence: 99%

Efficient DMFT impurity solver using real-time dynamics with matrix product states

et al. 2015

View full text Add to dashboard Cite

show abstract

“…617196). Part of the implementation is based on the TRIQS toolbox [63] and on the ALPS libraries [64].…”

Section: Acknowledgmentsmentioning

confidence: 99%

Influence of Fock exchange in combined many-body perturbation and dynamical mean field theory

et al. 2017

Self Cite

View full text Add to dashboard Cite

In electronic systems with long-range Coulomb interaction, the nonlocal Fock-exchange term has a bandwidening effect. While this effect is included in combined many-body perturbation theory and dynamical mean field theory (DMFT) schemes, it is not taken into account in standard extended DMFT (EDMFT) calculations. Here, we include this instantaneous term in both approaches and investigate its effect on the phase diagram and dynamically screened interaction. We show that the largest deviations between previously presented EDMFT and GW +EDMFT results originate from the nonlocal Fock term, and that the quantitative differences are especially large in the strong-coupling limit. Furthermore, we show that the charge-ordering phase diagram obtained in GW +EDMFT methods for moderate interaction values is very similar to the one predicted by dual-boson methods that include the fermion-boson or four-point vertex. DOI: 10.1103/PhysRevB.95.245130 Dynamical mean field theory (DMFT) [1] self-consistently maps a correlated Hubbard lattice problem with local interactions onto an effective impurity problem consisting of a correlated orbital hybridized with a noninteracting fermionic bath. If the bath is integrated out, one obtains an impurity action with retarded hoppings. Extended dynamical mean field theory [2-10] (EDMFT) extends the DMFT idea to systems with long-range interactions. It does so by mapping a lattice problem with long-range interactions onto an effective impurity model with self-consistently determined fermionic and bosonic baths, or, in the action formulation, an impurity model with retarded hoppings and retarded interactions.While EDMFT captures dynamical screening effects and charge-order instabilities, it has been found to suffer from qualitative shortcomings in finite dimensions. For example, the charge susceptibility computed in EDMFT does not coincide with the derivative of the average charge with respect to a small applied field [11], nor does it obey local charge conservation rules [12] essential for an adequate description of collective modes such as plasmons.The EDMFT formalism has an even more basic deficiency: since it is based on a local approximation to the self-energy, it does not include even the first-order nonlocal interaction term, the Fock term. The combined GW +EDMFT [13][14][15] scheme corrects this by supplementing the local self-energy from EDMFT with the nonlocal part of the GW diagram, where G is the interacting Green's function and W the fully screened interaction. Indeed, the nonlocal Fock term [Gv] nonloc is included in the nonlocal [GW ] nonloc diagram. As described in more detail in Ref. [15] (see also the appendix of Ref.[16]), the GW +EDMFT method is formally obtained by constructing an energy functional of G and W , the Almbladh [17] functional , and by approximating as a sum of two terms, one containing all local diagrams (corresponding to EDMFT) and the other containing the simplest nonlocal correction (corresponding to the GW approximation [18]). This functional construct...

show abstract

“…28 The DMFT calculations were performed using tools based on the triqs software package developed by Parcollet and Ferrero. 29 The V 3d subspace for the DMFT treatment was constructed from the allelectron electronic structure using the triqs/dfttools package. 30,31 The local Hamiltonian of the V 3d subspace has large off-diagonal elements, and the use of the continuous-time hybridization-expansion Monte Carlo solver triqs/cthyb written by Seth and Krivenko ameliorated the sign problem.…”

Section: Computational Detailsmentioning

confidence: 99%

Mott-to-Goodenough insulator-insulator transition inLiVO2

Subedi

2017

Phys. Rev. B

View full text Add to dashboard Cite

TRIQS: A toolbox for research on interacting quantum systems

Cited by 381 publications

References 19 publications

Efficient DMFT impurity solver using real-time dynamics with matrix product states

Efficient DMFT impurity solver using real-time dynamics with matrix product states

Influence of Fock exchange in combined many-body perturbation and dynamical mean field theory

Mott-to-Goodenough insulator-insulator transition inLiVO2

Contact Info

Product

Resources

About