Quantum coherence in single biomolecules measured by multidimensional optical micro-spectroscopy

生命是基于多种生物分子之间的复杂相互作用，包括脂质，蛋白质和DNA。它们在本质上是动态的，维持着生命的非平衡状态。为了理解生命的机制，分子之间的相互作用是长期进化的结果。虽然许多机制可以通过非平衡热力学利用具有空间浓度梯度的局部平衡来描述，但已经强调了一些例子，这些例子显示了分子复合物激发的量子相干性的重要性[10.1098/rsif.2018.0640]。特别是在感知（嗅觉、视觉）和光合作用的功能中，长程相干耦合（例如通过偶极-偶极相互作用）与局部振动耦合之间的相互作用是一种正在研究的有趣机制[10.1126/science.1235820]。基于导师实验室在发展先进激光显微光谱技术方面的开创性工作，本项目将研究单个生物分子功能单元的相干量子动力学。您将从半导体纳米结构的研究中翻译我们实验室开发和可用的二维相干显微光谱技术“外差光谱干涉术”[10.1038/ncomms 2764，0.1038/nphoton.2016.2]，朝着这一宏伟目标迈进。将研究从低温（5 K）到室温的光捕获复合物中的相干性的演变，在低温下，预期长寿命的相干性，在室温下，热激发减少相干时间，生物分子在其操作范围内。这将使您能够确定退相干的机制，并验证大自然是否在相关生物体（如藻类和硫磺/紫色细菌）的生活条件下优化了平衡。利用这一见解，我们计划在人工光捕获结构[10.1126/science.1249771]中研究这些相干性，这些结构正在被开发为绿色能源，以了解和优化其性能。

Life is based on the intricate interactions between a multitude of biomolecules, including lipids, proteins, and DNA. They are dynamical in nature and maintain the non-equilibrium state of life. To understand the machinery of life, the interactions between the molecules are finely tuned as a result of long-term evolution. While many mechanisms can be described by non-equilibrium thermodynamics making use of local equilibrium with spatial gradients of concentrations, some examples have been highlighted which show the importance of quantum coherence of excitations over molecular complexes [10.1098/rsif.2018.0640]. Specifically in the functions of sensing (smell, vision) and photosynthesis, the interplay between long range coherent coupling, e.g. via dipole-dipole interaction, and coupling to local vibrations, is an intriguing mechanism being investigated [10.1126/science.1235820]. Building on the pioneering work of the supervisor's laboratory in developing advanced laser micro-spectroscopy techniques, this project will investigate the coherent quantum dynamics of single biomolecule functional units.You will translate the two-dimensional coherent micro-spectroscopy technique "Heterodyne Spectral Interferometry", developed and available in our laboratory, from the investigations of semiconductor nanostructures [10.1038/ncomms2764, 0.1038/nphoton.2016.2], towards this ambitious goal. The evolution of the coherence in light-harvesting complexes will be studied from low temperatures (5K), where long lived coherence is expected, up to room temperature, where the thermal excitations reduce the coherence time and the biomolecules are in their operating range. This will allow you to identify the mechanisms of decoherence and verify if nature has tuned the balance optimally at living conditions of the related organisms, such as algae, and sulphur/purple bacteria. Using this insight, we plan to study these coherences in artificial light-harvesting structures [10.1126/science.1249771], which are being developed as a green energy source, in order to understand and optimize their performance.