  Quantum sensing utilizing unique quantum properties of non-Hermitian systems
to realize ultra-precision measurements has been attracting increasing
attention. However, the debate on whether non-Hermitian systems are superior to
Hermitian counterparts in sensing remains an open question. Here, we
investigate the quantum information in PT-symmetric quantum sensing utilizing
two experimental schemes based on the trapped-ion platform. It turns out that
the existence of advantages of non-Hermitian quantum sensing heavily depends on
additional information resources carried by the extra degrees of freedom
introduced to construct PT-symmetric quantum sensors. Moreover, the practical
application of non-Hermitian quantum sensing with superior performance is
primarily restricted by the additional resource consumption accompanied by the
post-selection. Our study provides theoretical references for the construction
of non-Hermitian quantum sensors with superior performance and has potential
applications in research fields of quantum precision measurement and quantum
information processing.
