  Solid-state spin defects are promising quantum sensors for a large variety of
sensing targets. Some of these defects couple appreciably to strain in the host
material. We propose to use this strain coupling for mechanically-mediated
dispersive single-shot spin readout by an optomechanically-induced transparency
measurement. Surprisingly, the estimated measurement times for
negatively-charged silicon-vacancy defects in diamond are an order of magnitude
shorter than those for single-shot optical fluorescence readout. Our scheme can
also be used for general parameter-estimation metrology and offers a higher
sensitivity than conventional schemes using continuous position detection.
