2025/08/06 by Kuklinski, Parker, Rempfer, Benjamin, Obenland, Kevin +1 · 1 citation
#FOS: Physical sciences #Quantum Physics (quant-ph)
paper · doi:10.48550/arxiv.2508.03987
The ability to efficiently state-prepare Gaussian distributions is critical to the success of numerous quantum algorithms. The most popular algorithm for this subroutine (Kitaev-Webb) has favorable polynomial resource scaling, however it faces enormous resource overheads making it functionally impractical. In this paper, we present a new, more intuitive method which uses exactly n-1 rotations, (n-1)(n-2)/2 two-qubit controlled rotations, and \lfloor(n-1)/2\rfloor ancilla to state-prepare an n-qubit Gaussian state. We then apply optimizations to the circuit to render it linear in T-depth. This method can be extended to state-preparations of complex functions with polynomial phase.