128 Identical Quantum Sources Integrated on a Single Silica Chip

Integrated photon sources play a key role in quantum information science, but source nonuniformity prevents all circuit elements from being connected coherently. The authors address this longstanding challenge via birefringence engineering and nonlinear interaction locking in femtosecond-laser direct writing, to yield 128 uniform quantum sources integrated in a single chip. These sources are tunable via different pumping regimes, for applications at large scale and high dimension in both discrete- and continuous-variable approaches. This demonstrated scalability and uniformity of quantum sources will enable large-scale all-on-chip quantum processors for real-world applications.