  Black phosphorene and its analogs have attracted intensive attention due to
their unique puckered structures, anisotropic characteristics, and negative
Poisson's ratio. The van der Waals heterostructures assembly by stacking
different materials may show novel physical properties which the parent
materials don't possess. In this work, the first-principles calculations were
performed to study the mechanical properties of the BP/SnSe van der Waals
heterostructure. Interestingly, a near-zero Poisson's ratio vzx was found in
BP/SnSe heterostructure. In addition, compared to the parent materials BP and
SnSe with strong in-plane anisotropic mechanical properties, the BP/SnSe
heterostructure shows strongly suppressed anisotropy. Our findings suggest that
the vdW heterostructure could show quite different mechanical properties from
the parent materials and provide new opportunities for the mechanical
applications of the heterostructures.
