  We present the ballistic quantum transport of a p-n-p bilayer silicene
junction in the presence of spin-orbit coupling and electric field using a
four-band model in combination with the transfer-matrix approach. A Mexican-hat
shape of the low-energy spectrum is observed similarly to bilayer graphene
under an interlayer bias. We show that while bilayer silicene shares some
physics with bilayer graphene, it has many intriguing phenomena that have not
been reported for the latter. First, the confined state producing a
significantly non-zero transmission in Mexican hat. Second, the cloaking of the
Mexican-hat confined state is found. Third, we observe that the Mexican-hat
cloaking results in a strong oscillation of conductance when the incident
energy is below the potential height. Finally, unlike monolayer silicene, the
conductance at large interlayer distances increases with the rise of electric
field when the incident energy is above the potential height.
