A derivation of Grover's algorithm for unstructured search, including phase inversion, inversion about the mean, and square-root query complexity.
Archive
2013
Part one of a three-post series on Shor's algorithm and its cryptographic applications, focused on period finding and RSA.
A derivation of the second-order coherence criterion for nonclassical light, explaining photon bunching, antibunching, sub-Poissonian statistics, and the Hanbury Brown-Twiss measurement.
A quantum cryptography protocol based on entangled photon pairs, using Bell-inequality tests to distribute a shared key and detect interception attempts.