title: Using non-Markovian measures to evaluate quantum master equations for photosynthesis.
abstract: When dealing with system-reservoir interactions in an open quantum system, such as a photosynthetic light-harvesting complex, approximations are usually made to obtain the dynamics of the system. One question immediately arises: how good are these approximations, and in what ways can we evaluate them? Here, we propose to use entanglement and a measure of non-Markovianity as benchmarks for the deviation of approximate methods from exact results. We apply two frequently-used perturbative but non-Markovian approximations to a photosynthetic dimer model and compare their results with that of the numerically-exact hierarchy equation of motion (HEOM). This enables us to explore both entanglement and non-Markovianity measures as means to reveal how the approximations either overestimate or underestimate memory effects and quantum coherence. In addition, we show that both the approximate and exact results suggest that non-Markonivity can, counter-intuitively, increase with temperature, and with the coupling to the environment.
authors.affiliation: Department of Physics and National Center for Theoretical Sciences, National Cheng Kung University, Tainan 701, Taiwan.
authors.forename: Hong-Bin
authors.initials: HB
authors.lastname: Chen
authors.affiliation: CEMS, RIKEN, Wako-shi, Saitama 351-0198, Japan.
authors.forename: Neill
authors.initials: N
authors.lastname: Lambert
authors.affiliation: Department of Chemistry and Center for Quantum Science and Engineering, National Taiwan University, Taipei 106, Taiwan.
authors.forename: Yuan-Chung
authors.initials: YC
authors.lastname: Cheng
authors.affiliation: Department of Physics and National Center for Theoretical Sciences, National Cheng Kung University, Tainan 701, Taiwan.
authors.forename: Yueh-Nan
authors.initials: YN
authors.lastname: Chen
authors.affiliation: 1] CEMS, RIKEN, Wako-shi, Saitama 351-0198, Japan [2] Physics Department, University of Michigan, Ann Arbor, Michigan 48109-1040, USA.
authors.forename: Franco
authors.initials: F
authors.lastname: Nori
mesh_terms: D019985:Benchmarking; D004735:Energy Transfer; D045342:Light-Harvesting Protein Complexes / Q000737:chemistry*; D008390:Markov Chains; D015233:Models, Statistical; D009038:Motion; D010788:Photosynthesis / Q000502:physiology*; D011789:Quantum Theory; D013696:Temperature; D013816:Thermodynamics
chemical_list: D045342:Light-Harvesting Protein Complexes