English
Related papers

Related papers: Multireference Correlation in Long Molecules with …

200 papers

We present an efficient implementation of a one-step relativistic second-order multireference perturbation theory based on the multireference driven similarity renormalization group (MR-DSRG) using the exact two-component (X2C) Hamiltonian,…

Chemical Physics · Physics 2026-05-13 Zijun Zhao , Francesco A. Evangelista

We develop an alternative time-dependent numerical renormalization group (TDNRG) formalism for multiple quenches and implement it to study the response of a quantum impurity system to a general pulse. Within this approach, we reduce the…

Strongly Correlated Electrons · Physics 2018-10-25 H. T. M. Nghiem , T. A. Costi

Wilson's Numerical Renormalization Group (NRG) is so far the only nonperturbative technique that can reliably access low-energy properties of quantum impurity systems. We present a recent extension of the method, the DM-NRG, which yields…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Walter Hofstetter

We present a simple method, combining the density-matrix renormalization-group (DMRG) algorithm with finite-size scaling, which permits the study of critical behavior in quantum spin chains. Spin moments and dimerization are induced by…

Strongly Correlated Electrons · Physics 2009-10-31 Shan-Wen Tsai , J. B. Marston

Several density-matrix renormalization group methods have been proposed to compute the momentum- and frequency-resolved dynamical correlation functions of low-dimensional strongly correlated systems. The most relevant approaches are…

Strongly Correlated Electrons · Physics 2009-01-28 Eric Jeckelmann

The GW approximation is a cornerstone of many-body perturbation theory for computing single-particle excitations, yet it fundamentally breaks down in strongly correlated systems where the single-reference picture fails. To overcome this…

Chemical Physics · Physics 2026-04-20 Yuqi Wang , Wei-Hai Fang , Zhendong Li

We discuss the development of an angular-momentum-conserving variant of the Density Matrix Renormalization Group (DMRG) method for use in large-scale shell-model calculations of atomic nuclei and report a first application of the method to…

Nuclear Theory · Physics 2009-02-09 B. Thakur , S. Pittel , N. Sandulescu

The density matrix renormalization group (DMRG) is a numerical method that optimizes a variational state expressed by a tensor product. We show that the ground state is not fully optimized as far as we use the standard finite system…

Statistical Mechanics · Physics 2010-05-20 H. Takasaki , T. Hikihara , T. Nishino

We propose a new approach to implement the density matrix renormalization group (DMRG) in two dimensions. With this approach the initial blocks of a L by L lattice are built up directly from the matrix elements of a (L-1) by L-1) lattice…

Strongly Correlated Electrons · Physics 2009-11-07 Tao Xiang , Jizhong Lou , Zhaobin Su

An efficient density matrix renormalization group (DMRG) algorithm is presented for the Bethe lattice with connectivity $Z = 3$ and antiferromagnetic exchange between nearest neighbor spins $s= 1/2$ or 1 sites in successive generations $g$.…

Strongly Correlated Electrons · Physics 2015-06-03 Manoranjan Kumar , S. Ramasesha , Zoltan G. Soos

We apply the DMRG method to the BCS pairing Hamiltonian which describes ultrasmall superconducting grains. Our version of the DMRG uses the particle (hole) states around the Fermi level as the system block (environment). We observe a smooth…

Superconductivity · Physics 2009-10-31 J. Dukelsky , G. Sierra

We use density-matrix renormalization group, applied to a one-dimensional model of continuum Hamiltonians, to accurately solve chains of hydrogen atoms of various separations and numbers of atoms. We train and test a machine-learned…

Strongly Correlated Electrons · Physics 2016-12-28 Li Li , Thomas E. Baker , Steven R. White , Kieron Burke

Strong-Disorder Renormalization Group (SDRG), despite being a relatively simple real-space renormalization procedure, provides in principle exact results on the critical properties at the infinite-randomness fixed point of random quantum…

Statistical Mechanics · Physics 2020-01-29 Christophe Chatelain

Dynamical electronic- and vibrational-structure theories have received a growing interest in the last years due to their ability to simulate spectra recorded with ultrafast experimental techniques. The exact time evolution of a molecular…

Computational Physics · Physics 2020-02-18 Alberto Baiardi , Markus Reiher

We develop a variant of the density matrix renormalization group (DMRG) algorithm for two-dimensional cylinders that uses a real space representation along the cylinder and a momentum space representation in the perpendicular direction. The…

Strongly Correlated Electrons · Physics 2016-04-25 Johannes Motruk , Michael P. Zaletel , Roger S. K. Mong , Frank Pollmann

We introduce a Lagrangian formulation of the Density Matrix Renormalization Group (DMRG). We present Lagrangians which when minimised yield the optimal DMRG wavefunction in a variational sense, both within the general matrix product ansatz,…

Strongly Correlated Electrons · Physics 2008-04-11 Garnet Kin-Lic Chan

We have applied the momentum space version of the Density Matrix Renormalization Group method ($k$-DMRG) in quantum chemistry in order to study the accuracy of the algorithm in the new context. We have shown numerically that it is possible…

Strongly Correlated Electrons · Physics 2009-02-06 O. Legeza , J. Roder , B. A. Hess

We present a method for computing resonant inelastic x-ray scattering (RIXS) spectra in one-dimensional systems using the density matrix renormalization group (DMRG) method. By using DMRG to address the problem, we shift the computational…

Strongly Correlated Electrons · Physics 2018-09-20 A. Nocera , U. Kumar , N. Kaushal , G. Alvarez , E. Dagotto , S. Johnston

The density-matrix renormalization group (DMRG) applied to transfer matrices allows it to calculate static as well as dynamical properties of one-dimensional quantum systems at finite temperature in the thermodynamic limit. To this end the…

Strongly Correlated Electrons · Physics 2007-12-20 S. Glocke , A. Klümper , J. Sirker

The polarizable embedding (PE) approach is a flexible embedding model where a pre-selected region out of a larger system is described quantum mechanically while the interaction with the surrounding environment is modeled through an…

Chemical Physics · Physics 2017-01-24 Erik D. Hedegård , Markus Reiher