Optical selection rules in monolayers of transition metal dichalcogenides and of their heterostructures are determined by the conservation of the z-component of the total angular momentum—J Z = L Z +S Z – associated with the C 3 rotational lattice symmetry which assumes half integer values corresponding, modulo 3, to distinct states. Here we show, based on polarization resolved and low temperature magneto-optical spectroscopy experiments, that the conservation of the total angular momentum in these systems leads to a very efficient exciton-phonon interaction when the coupling is mediated through chiral phonons. We identify these phonons as the Γ point E” modes which despite carrying angular momentum ± 1 are able to induce an excitonic spin-flip of ##IMG## [http://ej.iop.org/images/2053-1583/7/4/041002/tdmaba567ieqn1.gif] {$\mp2$} thanks to the C 3 symmetry. These experiments reveal ...

中文翻译：

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MoSe 2 / WSe 2异质双分子层中的手性声子翻转激子角动量

过渡金属二硫化碳单层及其异质结构的光学选择规则由总角动量的z分量（JZ = LZ + SZ）的守恒确定，该角分量与C 3旋转晶格对称性相关，并假设对应于一半整数值，模3，为不同的状态。在这里，我们基于偏振分辨和低温磁光光谱实验表明，当通过手性声子进行耦合时，这些系统中总角动量的守恒导致非常有效的激子-声子相互作用。我们将这些声子识别为Γ点E”模式，尽管携带了±1的角动量，它们仍能够引起## IMG ##的激子自旋翻转[http://ej.iop.org/images/2053-1583/ 7/4/041002 / tdmaba567ieqn1。gif] {$ \ mp2 $}多亏了C 3对称性。这些实验揭示了...