2015/04/30 by Eduardo Mascarenhas, H. Flayac, Hugo Flayac +1 · 7 citations
Computer Science · Mathematics · Physics and Astronomy · #Ansatz #Degenerate energy levels #Density matrix #Density matrix renormalization group #Dissipative system #Hamiltonian (control theory) #Mathematical optimization #Mathematics #Matrix multiplication #Matrix product state #Non-equilibrium thermodynamics #Operator (biology) #Physics #Quantum #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum many-body systems #Quantum mechanics #Quantum system #Statistical physics #cond-mat.mes-hall #quant-ph
paper · pdf · doi:10.1103/physreva.92.022116
published as Phys. Rev. A 92, 022116 (2015)
arxiv created 2015/07/14 · openalex publication_date 2015/08/19 · arxiv updated 2015/08/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We develop a numerical procedure to efficiently model the nonequilibrium steady state of one-dimensional arrays of open quantum systems based on a matrix-product operator ansatz for the density matrix. The procedure searches for the null eigenvalue of the Liouvillian superoperator by sweeping along the system while carrying out a partial diagonalization of the single-site stationary problem. It bears full analogy to the density-matrix renormalization-group approach to the ground state of isolated systems, and its numerical complexity scales as a power law with the bond dimension. The method brings considerable advantage when compared to the integration of the time-dependent problem via Trotter decomposition, as it can address arbitrarily long-ranged couplings. Additionally, it ensures numerical stability in the case of weakly dissipative systems thanks to a slow tuning of the dissipation rates along the sweeps. We have tested the method on a driven-dissipative spin chain, under various assumptions for the Hamiltonian, drive, and dissipation parameters, and compared the results to those obtained both by Trotter dynamics and Monte Carlo wave function methods. Accurate and numerically stable convergence was always achieved when applying the method to systems with a gapped Liouvillian and a nondegenerate steady state.