Fig. (4)
(
a
) 3C-HHall with a single mirror symmetry axis Re{z}. (
b
) Its conformal transformation on the upper half of the
w
' -plane has 3 electrical DoF
k
12
,
k
23
,
R
sh
. (
c
) Its ERC has only 2 electrical DoF
R
d
,
R
e
.
