Optimization of coherent energy transfer in light-harvesting systems |
|
| Jianshu Cao | |
| Massachusetts Institute of Technology, Cambridge | |
| Energy transfer in photosynthesis is the initial step in the conversion of solar energy into chemical energy for human consumption. This talk will discuss the optimal conditions under which photosynthetic light-harvesting systems can achieve maximal energy transfer efficiency, i.e., the maximal exciton mobility. (1) A simple scaling theory is developed to explain the optimal energy transfer efficiency, as a function of temperature, noise level, and solvent relaxation time-scale, and its dependence on the initial state preparation due to photo-excitation. (2) A perturbation technique is then developed on the basis of NIBA (non-interaction blip approximation) to systematically map a quantum network to a kinetic network, where the leading order is hopping and higher order corrections contribute non-local quantum effects. (3) The role of intrinsic symmetry in exciton systems regarding the efficient and robust of light-harvesting energy transfer is demonstrated for LH2 B850 rings. These results provide useful insight to the process of natural selection in light-harvesting systems and to the principles of optimal design principles of light-harvesting energy devices.
References: |