  Optical trapping and binding systems are non-Hermitian. On one hand, the
optical force is non-Hermitian and may pump energy into the trapped particle
when the non-Hermiticity is sufficiently large. On the other hand, the ambient
damping constitutes a loss to the particle. Here, we show that in a
low-friction environment, the interplay between the energy pumped-in by light
and the ambient dissipation can give rise to either instability or a periodic
vibration characterized by a finite quality factor (Q-factor). Through a
comprehensive exploration, we analyze the influence of various parameters on
the non-Hermitian force field. Our investigation reveals several strategies for
enhancing the non-Hermitian force field, such as augmenting particle radius and
refractive index, utilizing triangular lattice optical clusters, and reducing
lattice constants.
