  We study the distribution and generation of quantum coherence for two-mode
and multi-mode Gaussian states in de Sitter space. It is found that the quantum
coherence is redistributed among the mode in different open charts under the
curvature effect of de Sitter space. In particular, the Gaussian coherence for
the initially correlated state is found to survive in the limit of infinite
curvature, while quantum entanglement vanishing in this limit. Unlike
entanglement and steering, the coherence of a massive scalar field is more
robust than a massless field under the influence of curvature of de Sitter
space. In addition, it is shown that the curvature generates two-mode Gaussian
state and three-mode Gaussian state quantum coherence among the open charts,
even though the observers are localized in causally disconnected regions. It is
worth noting that the gravity-generated three-mode coherence is extremely
sensitive to the curvature effect for the conformal and massless scalar fields,
which may be in principle employed to design an effective detector for the
space curvature.
