M-ary state phase-shift keying discrimination below the homodyne limit
Francisco E. Becerra Chavez, Jingyun Fan, Gerald Baumgartner, Sergey V. Polyakov, Julius Goldhar, Jonathan Kosloski, Alan L. Migdall
We investigate a strategy for M-ary discrimination of nonorthogonal phase states with error rates below the homodyne limit. This strategy uses feed forward to update a reference ﬁeld and Signal nulling for the state discrimination. We experimentally analyze the receiver performance using postprocessing and a Bayesian strategy to emulate the feed-forward process. This analysis demonstrates that for a moderate system detection eﬃciency, it is possible to surpass the homodyne error limit for quadrature phase-shift keying (QPSK) signals using feed forward.
, Fan, J.
, Baumgartner, G.
, Polyakov, S.
, Goldhar, J.
, Kosloski, J.
and Migdall, A.
M-ary state phase-shift keying discrimination below the homodyne limit, Physical Review A, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=908874
(Accessed January 23, 2022)