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arXiv · 0903.2936

Coherent control of an effective two-level system in a non-Markovian biomolecular environment

Jens Eckel·John Henry Reina·Michael Thorwart
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Abstract

We investigate the quantum coherent dynamics of an externally driven effective two-level system subjected to a slow Ohmic environment characteristic of biomolecular protein-solvent reservoirs in photosynthetic light harvesting complexes. By means of the numerically exact quasi adiabatic propagator path integral (QUAPI) method we are able to include non-Markovian features of the environment and show the dependence of the quantum coherence on the characteristic bath cut-off frequency omega_c as well as on the driving frequency omega_l and the field amplitude A. Our calculations extend from the weak coupling regime to the incoherent strong coupling regime. In the latter case, we find evidence for a resonant behaviour, beyond the expected behaviour, when the reorganization energy E_r coincides with the driving frequency. Moreover, we investigate how the coherent destruction of tunneling within the two-level system is influenced by the non-Markovian environment.

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Jens Eckel, John Henry Reina, Michael Thorwart. 2009-08-19. Coherent control of an effective two-level system in a non-Markovian biomolecular environment. https://doi.org/10.1088/1367-2630%2F11%2F8%2F085001

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