RT Journal Article
SR Electronic
T1 Quantum interference enables constant-time quantum information processing
JF Science Advances
JO Sci Adv
FD American Association for the Advancement of Science
SP eaau9674
DO 10.1126/sciadv.aau9674
VO 5
IS 7
A1 StobiĆska, M.
A1 Buraczewski, A.
A1 Moore, M.
A1 Clements, W. R.
A1 Renema, J. J.
A1 Nam, S. W.
A1 Gerrits, T.
A1 Lita, A.
A1 Kolthammer, W. S.
A1 Eckstein, A.
A1 Walmsley, I. A.
YR 2019
UL http://advances.sciencemag.org/content/5/7/eaau9674.abstract
AB It is an open question how fast information processing can be performed and whether quantum effects can speed up the best existing solutions. Signal extraction, analysis, and compression in diagnostics, astronomy, chemistry, and broadcasting build on the discrete Fourier transform. It is implemented with the fast Fourier transform (FFT) algorithm that assumes a periodic input of specific lengths, which rarely holds true. A lesser-known transform, the Kravchuk-Fourier (KT), allows one to operate on finite strings of arbitrary length. It is of high demand in digital image processing and computer vision but features a prohibitive runtime. Here, we report a one-step computation of a fractional quantum KT. The quantum d-nary (qudit) architecture we use comprises only one gate and offers processing time independent of the input size. The gate may use a multiphoton Hong-Ou-Mandel effect. Existing quantum technologies may scale it up toward diverse applications.