English
Related papers

Related papers: Dynamical Spectral Function From Numerical Renorma…

200 papers

We show how the density-matrix numerical renormalization group (DM-NRG) method can be used in combination with non-Abelian symmetries such as SU(N), where the decomposition of the direct product of two irreducible representations requires…

Strongly Correlated Electrons · Physics 2012-11-28 Catalin Pascu Moca , Arne Alex , Jan von Delft , Gergely Zarand

We present a unified framework for renormalization group methods, including Wilson's numerical renormalization group (NRG) and White's density-matrix renormalization group (DMRG), within the language of matrix product states. This allows…

Strongly Correlated Electrons · Physics 2009-10-14 A. Weichselbaum , F. Verstraete , U. Schollwöck , J. I. Cirac , Jan von Delft

We present two new methods for performing ab initio calculations of excited states for closed-shell systems within the in-medium similarity renormalization group (IMSRG) framework. Both are based on combining the IMSRG with simple many-body…

Nuclear Theory · Physics 2017-05-10 N. M. Parzuchowski , T. D. Morris , S. K. Bogner

We present a pedagogical introduction to the In-Medium Similarity Renormalization Group (IM-SRG) framework for ab initio calculations of nuclei. The IM-SRG performs continuous unitary transformations of the nuclear many-body Hamiltonian in…

Nuclear Theory · Physics 2016-12-28 H. Hergert

We present a novel scheme for an unbiased and non-perturbative treatment of strongly correlated fermions. The proposed approach combines two of the most successful many-body methods, i.e., the dynamical mean field theory (DMFT) and the…

Strongly Correlated Electrons · Physics 2014-05-27 C. Taranto , S. Andergassen , J. Bauer , K. Held , A. Katanin , W. Metzner , G. Rohringer , A. Toschi

Non-Hermitian (NH) Hamiltonians describe open quantum systems, nonequilibrium dynamics, and dissipative processes. Although a rich range of single-particle NH physics has been uncovered, many-body phenomena in strongly correlated NH systems…

Strongly Correlated Electrons · Physics 2026-03-05 Phillip C. Burke , Andrew K. Mitchell

Random noncommutative geometry can be seen as a Euclidean path-integral approach to the quantization of the theory defined by the Spectral Action in noncommutative geometry (NCG). With the aim of investigating phase transitions in random…

Mathematical Physics · Physics 2021-08-10 Carlos I. Perez-Sanchez

Within the Functional Renormalisation Group (FRG) approach, we present a fluid-dynamical approach to solving flow equations for models living in a multi-dimensional field space. To this end, the underlying exact flow equation of the…

Statistical Mechanics · Physics 2024-12-23 Niklas Zorbach , Adrian Koenigstein , Jens Braun

We apply the DMRG method to the 2 dimensional delta function potential which is a simple quantum mechanical model with asymptotic freedom and formation of bound states. The system block and the environment block of the DMRG contain the low…

High Energy Physics - Theory · Physics 2009-10-31 M. A. Martin-Delgado , G. Sierra

We use the numerical renormalization group method (NRG) to investigate a single-impurity Anderson model with a coupling of the impurity to a superconducting host. Analysis of the energy flow shows, in contrast to previous belief, that NRG…

Strongly Correlated Electrons · Physics 2015-05-13 Theresa Hecht , Andreas Weichselbaum , Jan von Delft , Ralf Bulla

Variational approaches for the calculation of vibrational wave functions and energies are a natural route to obtain highly accurate results with controllable errors. However, the unfavorable scaling and the resulting high computational cost…

Chemical Physics · Physics 2017-08-14 Alberto Baiardi , Christopher J. Stein , Vincenzo Barone , Markus Reiher

We use the functional Renormalisation Group (fRG) to describe the in and out of equilibrium dynamics of stochastic processes, governed by an overdamped Langevin equation. Exploiting the connection between Langevin dynamics and…

Statistical Mechanics · Physics 2021-02-05 Ashley Wilkins , Gerasimos Rigopoulos , Enrico Masoero

We have extended the density matrix renormalization group (DMRG) approach to two-fluid open many-fermion systems governed by complex-symmetric Hamiltonians. The applications are carried out for three- and four-nucleon (proton-neutron)…

Nuclear Theory · Physics 2009-01-22 J. Rotureau , N. Michel , W. Nazarewicz , M. Ploszajczak , J. Dukelsky

A new approach to large-scale nuclear structure calculations, based on the Density Matrix Renormalization Group (DMRG), is described. The method is tested in the context of a problem involving many identical nucleons constrained to move in…

Nuclear Theory · Physics 2011-05-12 J. Dukelsky , S. Pittel

We describe the generalization of Wilson's Numerical Renormalization Group method to quantum impurity models with a bosonic bath, providing a general non-perturbative approach to bosonic impurity models which can access exponentially small…

Statistical Mechanics · Physics 2007-05-23 Ralf Bulla , Ning-Hua Tong , Matthias Vojta

We generalize the spectral sum rule preserving density matrix numerical renormalization group (DM-NRG) method in such a way that it can make use of an arbitrary number of not necessarily Abelian, local symmetries present in the quantum…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 A. I. Toth , C. P. Moca , O. Legeza , G. Zarand

We show that the numerical renormalization group (NRG) is a viable multi-band impurity solver for Dynamical Mean Field Theory (DMFT), offering unprecedent real-frequency spectral resolution at arbitrarily low energies and temperatures. We…

Strongly Correlated Electrons · Physics 2015-09-30 K. M. Stadler , A. Weichselbaum , Z. P. Yin , J. von Delft , G. Kotliar

The density matrix renormalization group (DMRG) is applied to some one-dimensional reaction-diffusion models in the vicinity of and at their critical point. The stochastic time evolution for these models is given in terms of a non-symmetric…

Statistical Mechanics · Physics 2011-10-11 Enrico Carlon , Malte Henkel , Ulrich Schollwoeck

In this work, we simulate the electron dynamics in molecular systems with the Time-Dependent Density Matrix Renormalization Group (TD-DMRG) algorithm. We leverage the generality of the so-called tangent-space TD-DMRG formulation and design…

Chemical Physics · Physics 2021-06-08 Alberto Baiardi

The full-density-matrix numerical renormalization group (NRG) has evolved as a systematic and transparent setting for the cal- culation of thermodynamical quantities at arbitrary temperatures within the NRG framework. It directly evaluates…

Strongly Correlated Electrons · Physics 2013-05-30 Andreas Weichselbaum