We study the Andreev reflections (ARs) at the interface of the type-II Weyl
semimetal-superconductor junctions and find double ARs when the superconductor
is put in the Weyl semimetal band tilting direction, which is similar to the
double reflections of light in anisotropic crystals. The directions of the
double (retro and specular) ARs are symmetric about the normal due to the
hyperboloidal Fermi surface near the Weyl nodes, but with different AR
amplitudes depending on the direction and energy of the incident electron. When
the normal direction of the Weyl semimetal-superconductor interface is changed
from parallel to perpendicular with the tilt direction, the double ARs
gradually evolve from one retro-AR and one specular AR, passing through double
retro-ARs, one specular AR and one retro-AR, into one retro AR and one normal
reflection, resulting in an anisotropic conductance which can be observed in
experiments.Comment: 12 pages, 7 figure
