  The bulk boundary correspondence in the context of Weyl semimetals is a
fundamental topological principle that establishes a connection between the
bulk properties of the material and the emergence of specific surface states.
In Weyl semimetals, the bulk boundary correspondence is manifested by the
presence of surface Fermi arcs connecting pairs of Weyl nodes with opposite
chirality. Here we demonstrate that this bulk boundary correspondence is
challenged in the case of the surface selectively reconstructed
noncentrosymmetric magnetic Weyl semimetal NdAlSi. By comparing angle-resolved
photoemission spectroscopy measurements with surface projected density
functional theory calculations and scanning tunneling microscope measurements,
the existence of surface selective spontaneous reconstruction is demonstrated.
The surface reconstruction in NdAlSi not only leads to the reconstruction of
the surface Fermi arcs, but also generates new surface Fermi arcs that do not
connect corresponding Weyl nodes. This observation challenges the conventional
view of the bulk boundary correspondence in Weyl semimetals.
