Randomness Enhancement in a Quantum Dot-Based Quantum Random Number Generator by Correctors

In this work, we analyze the randomness of a bit stream generated by a quantum dot-based quantum random number generator (QRNG) implemented by a noisy Hadamard gate. We observe that the decoherence of the physical system affects the randomness of the bit stream. Further, to enhance the randomness, we employ various linear corrector functions, which (in theory) act on an input string of bits to give an output string of bits with improved randomness. We use certain tests recommended by NIST to characterize the randomness of the generated and the corrected bit strings. A comparison of these test results shows that linear correctors with high
$t$
values (around 16) can enhance the randomness of the bit strings generated by a noisy quantum random number generator (QRNG). Therefore, even a noisy QRNG, when combined with an appropriate corrector, will make such devices feasible for true random number generators. This randomness enhancement comes at the cost of reduced bit rates and potential computation time overheads for the QRNG.