Boulatov Alexei, Burin Alexander L
National Research University Higher School of Economics, 11 Pokrovsky Blvd., Moscow 101000, Russia.
Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, USA.
J Chem Phys. 2020 Oct 7;153(13):134102. doi: 10.1063/5.0018591.
The low temperature transport of electron, or vibrational or electronic exciton toward polymer chains, turns out to be dramatically sensitive to its interaction with transverse acoustic vibrations. We show that this interaction leads to a substantial polaron effect and decoherence, which are generally stronger than those associated with longitudinal vibrations. For site-dependent interactions, transverse phonons form subohmic bath leading to the quantum phase transition accompanied by full suppression of the transport at zero temperature and fast decoherence characterized by temperature dependent rate k ∝ T at low temperature, while k ∝ T for site-independent interactions. The latter dependence was used to interpret recent measurements of temperature dependent vibrational energy transport in polyethylene glycol oligomers.
电子、振动或电子激子向聚合物链的低温输运，结果表明对其与横向声振动的相互作用极为敏感。我们表明，这种相互作用会导致显著的极化子效应和退相干，通常比与纵向振动相关的效应更强。对于与位置有关的相互作用，横向声子形成亚欧姆浴，导致量子相变，同时在零温度下完全抑制输运，在低温下以与温度相关的速率k ∝ T为特征快速退相干，而对于与位置无关的相互作用，k ∝ T。后者的依赖关系被用于解释最近对聚乙二醇低聚物中与温度相关的振动能量输运的测量。
