  The quest for an integrated quantum optics platform has motivated the field
of semiconductor quantum dot research for two decades. Demonstrations of
quantum light sources, single photon switches, transistors, and spin-photon
interfaces have become very advanced. Yet the fundamental problem that every
quantum dot is different prevents integration and scaling beyond a few quantum
dots. Here, we address this challenge by patterning strain via local phase
transitions to selectively tune individual quantum dots that are embedded in a
photonic architecture. The patterning is implemented with in operando laser
crystallization of a thin HfO$_{2}$ film "sheath" on the surface of a GaAs
waveguide. Using this approach, we tune InAs quantum dot emission energies over
the full inhomogeneous distribution with a step size down to the homogeneous
linewidth and a spatial resolution better than 1 $\mu $m. Using these
capabilities, we tune multiple quantum dots into resonance within the same
waveguide and demonstrate a quantum interaction via superradiant emission from
three quantum dots.
