Fast quantum interference of a nanoparticle via optical potential control

Significance Testing the quantum superposition principle for large delocalization and increasingly massive objects is one of the grand challenges of modern quantum experiments. Levitated solid-state particles have recently emerged as a promising system to achieve this. In this work, we introduce an experimental method to generate center-of-mass superposition states at previously unattainable mass-, length- and time scales using only external optical and electrostatic potentials. We analyze relevant decoherence mechanisms and show the feasibility of observing quantum interference of a largely delocalized 100-nm silica particle at room temperature and with available state-of-the-art technology. Our results provide a route to experimentally realizing quantum superpositions of large mass and macroscopic separation.