O NMR spectroscopy has been the subject of vivid interest in recent years, because there is increasing evidence that it can provide unique insight into the structure and reactivity of many molecules and materials. However, due to the very poor natural abundance of oxygen-17, O labeling is generally a prerequisite. This is a real obstacle for most research groups, because of the high costs and/or strong experimental constraints of the most frequently used O-labeling schemes. Here, we show for the first time that mechanosynthesis offers unique opportunities for enriching in O a variety of organic and inorganic precursors of synthetic interest. The protocols are fast, user-friendly, and low-cost, which makes them highly attractive for a broad research community, and their suitability for O solid-state NMR applications is demonstrated.

We investigate polarization properties of neutral exciton emission in single self-assembled InAs/GaAs quantum dots. The in-plane shape and strain anisotropy strongly couple the heavy and light hole states and lead to large optical anisotropy with non-orthogonal linearly polarized states misaligned with respect to the crystallographic axes. Owing to a waveguiding experimental configuration, luminescence polarization along the growth axis has been observed revealing the presence of shear components of the deformation tensor out of the growth plane. Resonant luminescence experiments allowed determining the oscillator strength ratio of the two exciton eigenstates. Valence band mixing governs this ratio and can be very different from dot to dot, however the polarization anisotropy axis is quite fixed inside a scanned area of one µm 2 and indicates that the in-plane deformation direction to which it is related has a correlation length of the order of magnitude of one µm 2 .

. Probing electron-phonon interaction through twophoton interference in resonantly driven semiconductor quantum dots. Physical Review Letters, 118, [233602] University of Bristol -Explore Bristol Research General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: