Single photons via quantum dot excitation using a narrowband tunable fiber laser

We present a turn-key portable picosecond fiber laser for efficient quantum dot excitation to generate single photons. The laser combines a mode-hop-free tunability in the regions 770-980 nm and 1150-1500 nm with a high pulse-to-pulse coherence of 98%. A high single photon purity and indistinguishability were demonstrated. An excellent long-term power stability with a standard deviation of less than 0.3% and wavelength stability of better than 5 pm were achieved. The laser enables excitation of different semiconductor quantum dots and excitation schemes, essential for versatile easy-to-use single-photon sources based on quantum dots for research applications and commercial quantum computing.