  We report on two-photon interference (TPI) experiments using remote
deterministic single-photon sources. Employing 3D in-situ electron-beam
lithography, we fabricate quantum-light sources at specific target wavelengths
by integrating pre-selected semiconductor quantum dots within monolithic
microlenses. The individual single-photon sources show TPI visibilities of 49%
and 22%, respectively, under pulsed p-shell excitation at 80 MHz. For the
mutual TPI of the remote sources, we observe an uncorrected visibility of 29%,
in quantitative agreement with the pure dephasing of the individual sources.
Due to its efficient photon extraction within a broad spectral range (> 20 nm),
our microlens-based approach is predestinated for future entanglement swapping
experiments utilizing entangled photon pairs emitted by distant
biexciton-exciton radiative cascades.
