PT Journal
AU Linowski, T
   Schlichtholz, K
   Sorelli, G
   Gessner, M
   Walschaers, M
   Treps, N
   Rudnicki, L
TI Application range of crosstalk-affected spatial demultiplexing for resolving separations between unbalanced sources
SO New Journal of Physics
JI New J. Phys.
PY 2023
BP 103050
EP 13pp
VL 25
IS 10
DI 10.1088/1367-2630/ad0173
LA English
DE super resolution; spatial demultiplexing; crosstalk; unbalanced sources; Fisher information; measurement precision
AB Super resolution is one of the key issues at the crossroads of contemporary quantum optics and metrology. Recently, it was shown that for an idealized case of two balanced sources, spatial mode demultiplexing (SPADE) achieves resolution better than direct imaging even in the presence of measurement crosstalk (Gessner et al 2020 Phys. Rev. Lett. 125 100501). In this work, we consider arbitrarily unbalanced sources and provide a systematic analysis of the impact of crosstalk on the resolution obtained from SPADE. As we dissect, in this generalized scenario, SPADE's effectiveness depends non-trivially on the strength of crosstalk, relative brightness and the separation between the sources. In particular, for any source imbalance, SPADE performs worse than ideal direct imaging in the asymptotic limit of vanishing source separations. Nonetheless, for realistic values of crosstalk strength, SPADE is still the superior method for several orders of magnitude of source separations.
ER