6533b7d2fe1ef96bd125f839
RESEARCH PRODUCT
Entanglement continuous unitary transformations
Roman OrusKai Phillip SchmidtSerkan Sahinsubject
PhysicsQuantum PhysicsStrongly Correlated Electrons (cond-mat.str-el)High Energy Physics - Lattice (hep-lat)FOS: Physical sciencesGeneral Physics and AstronomyQuantum entanglement01 natural sciencesSecond quantizationMatrix multiplication010305 fluids & plasmasCondensed Matter - Strongly Correlated Electronssymbols.namesakeTheoretical physicsHigh Energy Physics - Lattice0103 physical sciencesThermodynamic limitsymbolsIsing modelQuantum Physics (quant-ph)010306 general physicsHamiltonian (quantum mechanics)QuantumPotts modeldescription
Continuous unitary transformations are a powerful tool to extract valuable information out of quantum many-body Hamiltonians, in which the so-called flow equation transforms the Hamiltonian to a diagonal or block-diagonal form in second quantization. Yet, one of their main challenges is how to approximate the infinitely-many coupled differential equations that are produced throughout this flow. Here we show that tensor networks offer a natural and non-perturbative truncation scheme in terms of entanglement. The corresponding scheme is called "entanglement-CUT" or eCUT. It can be used to extract the low-energy physics of quantum many-body Hamiltonians, including quasiparticle energy gaps. We provide the general idea behind eCUT and explain its implementation for finite 1d systems using the formalism of matrix product operators. We also present proof-of-principle results for the spin-1/2 1d quantum Ising model and the 3-state quantum Potts model in a transverse field. Entanglement-CUTs can also be generalized to higher dimensions and to the thermodynamic limit.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-07-15 | EPL (Europhysics Letters) |