Optimized Tensor-Network Renormalization for Quantum Dynamics: Resolving the Spectral Function of $\mathrm{K_2Co(SeO_3)_2}$

• URL: http://arxiv.org/abs/2608.02473v1
• Date: Mon, 03 Aug 2026 16:42:21 GMT
• Title: Optimized Tensor-Network Renormalization for Quantum Dynamics: Resolving the Spectral Function of $\mathrm{K_2Co(SeO_3)_2}$
• Abstract summary: We introduce an excitation-tailored corner-transfer-matrix renormalization-group (ET-CTMRG) method to resolve instability.<n>By incorporating excitation tensors into the renormalization procedure, the method constructs a substantially more accurate effective Hamiltonian matrix.<n>ET-CTMRG provides a robust framework for investigating the dynamical properties of strongly correlated quantum systems.
• Score: 1.7689281217287647
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Tensor-network methods have opened a powerful route for the study of dynamical spectral functions in two-dimensional quantum systems. However, existing approaches within the framework of infinite projected entangled-pair states construct the required renormalization tensors solely from the ground-state environment and can suffer from severe numerical instability. We identify the origin of this instability and introduce an excitation-tailored corner-transfer-matrix renormalization-group (ET-CTMRG) method to resolve it. By incorporating excitation tensors into the renormalization procedure, the method constructs a substantially more accurate effective Hamiltonian matrix and thereby yields reliable and well-converged excitation spectra. For Heisenberg antiferromagnets, it reduces truncation errors by orders of magnitude and for the particularly complex case of the supersolid phase in the triangular-lattice XXZ magnet $\mathrm{K_2Co(SeO_3)_2}$, it achieves excellent quantitative agreement with inelastic neutron-scattering measurements. ET-CTMRG therefore provides a robust framework for investigating the dynamical properties of strongly correlated quantum systems.

Related papers

• A first-principles linear response theory for open quantum systems and its application to Orbach and direct magnetic relaxation in Ln-based coordination polymers [39.146761527401424]
  Single-Molecule Magnets (SMMs) exhibit slow magnetic relaxation as a result of axial magnetic anisotropy inhibiting spin-phonon transitions.<n>We numerically implement a first-principles linear-response theory for open quantum systems that provides access to the complex a.c. magnetic susceptibility.
  arXiv  Detail & Related papers  (2026-03-19T10:19:50Z)
• Continuum field theory of matchgate tensor network ensembles [36.94429692322632]
  We develop a continuum description for random ensembles of two-dimensional fermionic matchgate tensor networks.<n>As a diagnostic of the resulting universal physics, we analyze disorder-averaged moments of fermionic two-point functions.<n>We show that disorder drives universal long-distance behavior governed by a nonlinear sigma-model of symmetry class D with a topological term.
  arXiv  Detail & Related papers  (2026-03-06T12:15:35Z)
• Quantum spectroscopy of topological dynamics via a supersymmetric Hamiltonian [0.0]
  We estimate topological descriptors through quantum spectroscopy.<n>We show that low-lying excited states quantify the stability of topological features.<n>This framework suggests that quantum hardware can function as a spectrometer for data topologies beyond classical reach.
  arXiv  Detail & Related papers  (2025-11-28T13:25:26Z)
• When Less is More: Approximating the Quantum Geometric Tensor with Block Structures [43.39839287869652]
  We introduce a block-diagonal quantum geometric tensor that partitions the metric by network layers, analogous to block-structured Fisher methods such as K-FAC.<n> Experiments on Heisenberg and frustrated $J_1$-$J$ models show faster convergence, lower energy, and improved stability.
  arXiv  Detail & Related papers  (2025-10-09T16:44:30Z)
• Molecular Properties in Quantum-Classical Auxiliary-Field Quantum Monte Carlo: Correlated Sampling with Application to Accurate Nuclear Forces [1.2189422792863451]
  We extend correlated sampling from classical auxiliary-field quantum Monte Carlo to the quantum-classical (QCAFQMC) framework.<n>We demonstrate significant improvements over single-reference methods in force evaluations for N$ wave$ and stretched linear H$_4$, particularly in strongly correlated regions.<n>We also apply our methodology to the MEA-CO$$ carbon capture reaction, employing quantum information metrics for active space selection and matchgate shadows.
  arXiv  Detail & Related papers  (2025-07-23T23:51:10Z)
• Symmetrizing the Constraints -- Density Matrix Renormalization Group for Constrained Lattice Models [0.40964539027092917]
  We develop a density matrix renormalization group (DMRG) algorithm for constrained quantum lattice models.<n>Such an implementation allows us to investigate a quantum dimer model in DMRG for any lattice geometry wrapped around a cylinder with substantial circumference.
  arXiv  Detail & Related papers  (2025-04-05T03:05:11Z)
• A Floquet-Rydberg quantum simulator for confinement in $\mathbb{Z}_2$ gauge theories [44.99833362998488]
  Recent advances in the field of quantum technologies have opened up the road for the realization of small-scale quantum simulators. We present a scalable Floquet scheme for the quantum simulation of the real-time dynamics in a $mathbbZ$ LGT. We show that an observation of gauge-invariant confinement dynamics in the Floquet-Rydberg setup is at reach of current experimental techniques.
  arXiv  Detail & Related papers  (2023-11-28T13:01:24Z)
• Efficient Quantum Analytic Nuclear Gradients with Double Factorization [0.0]
  We report a Lagrangian-based approach for evaluating relaxed one- and two-particle reduced density matrices from double factorized Hamiltonians. We demonstrate the accuracy and feasibility of our Lagrangian-based approach to recover all off-diagonal density matrix elements in classically-simulated examples.
  arXiv  Detail & Related papers  (2022-07-26T18:47:48Z)
• Calculating non-linear response functions for multi-dimensional electronic spectroscopy using dyadic non-Markovian quantum state diffusion [68.8204255655161]
  We present a methodology for simulating multi-dimensional electronic spectra of molecular aggregates with coupling electronic excitation to a structured environment. A crucial aspect of our approach is that we propagate the NMQSD equation in a doubled system Hilbert space but with the same noise.
  arXiv  Detail & Related papers  (2022-07-06T15:30:38Z)
• Decimation technique for open quantum systems: a case study with driven-dissipative bosonic chains [62.997667081978825]
  Unavoidable coupling of quantum systems to external degrees of freedom leads to dissipative (non-unitary) dynamics. We introduce a method to deal with these systems based on the calculation of (dissipative) lattice Green's function. We illustrate the power of this method with several examples of driven-dissipative bosonic chains of increasing complexity.
  arXiv  Detail & Related papers  (2022-02-15T19:00:09Z)
• Variational Quantum Simulation of Valence-Bond Solids [0.0]
  We introduce a hybrid quantum-classical variational algorithm to simulate ground-state phase diagrams of frustrated quantum spin models. We benchmark the method against the J1-J2 Heisenberg model on the square lattice and uncover its phase diagram. Our results show that the convergence of the algorithm is guided by the onset of long-range order, opening a promising route to synthetically realize frustrated quantum magnets.
  arXiv  Detail & Related papers  (2022-01-07T17:05:14Z)
• Quantum transport and localization in 1d and 2d tight-binding lattices [39.26291658500249]
  Particle transport and localization phenomena in condensed-matter systems can be modeled using a tight-binding lattice Hamiltonian. Here, we experimentally study quantum transport in one-dimensional and two-dimensional tight-binding lattices, emulated by a fully controllable $3 times 3$ array of superconducting qubits.
  arXiv  Detail & Related papers  (2021-07-11T12:36:12Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.