  The entropy or randomness source is an essential ingredient in random number
generation. Quantum random number generators generally require well modeled and
calibrated light sources, such as a laser, to generate randomness. With
uncharacterized light sources, such as sunlight or an uncharacterized laser,
genuine randomness is practically hard to be quantified or extracted owing to
its unknown or complicated structure. By exploiting a recently proposed
source-independent randomness generation protocol, we theoretically modify it
by considering practical issues and experimentally realize the modified scheme
with an uncharacterized laser and a sunlight source. The extracted randomness
is guaranteed to be secure independent of its source and the randomness
generation speed reaches 1 Mbps, three orders of magnitude higher than the
original realization. Our result signifies the power of quantum technology in
randomness generation and paves the way to high-speed semi-self-testing quantum
random number generators with practical light sources.
