Abstract
A
bstract
By introducing an extra stack of D6-branes to standard
$$ \mathcal{N} $$
N
= 1 supersymmetric Pati-Salam models, we extend the landscape of its complete search. In this construction, the
d
-stack of D6-branes is introduced besides the standard
a
,
b
,
c
-stacks. More intersections from the extra stacks of D6-branes appear, and thus Higgs/Higgs-like particles arise from more origins. Among these models, we complete with 28 classes of
$$ \mathcal{N} $$
N
= 1 supersymmetric Pati-Salam models under gauge symmetries
SU
(4)
C
×
SU
(2)
L
×
$$ SU{(2)}_{R_1} $$
SU
2
R
1
×
$$ SU{(2)}_{R_2} $$
SU
2
R
2
and
SU
(4)
C
×
$$ SU{(2)}_{L_1} $$
SU
2
L
1
×
SU
(2)
R
×
$$ SU{(2)}_{L_2} $$
SU
2
L
2
, where
d
-stack of D6-branes carries the gauge symmetries
$$ SU{(2)}_{R_2} $$
SU
2
R
2
and
$$ SU{(2)}_{L_2} $$
SU
2
L
2
, respectively. The
$$ SU{(2)}_{L_1/{R}_1} $$
SU
2
L
1
/
R
1
×
$$ SU{(2)}_{L_2/{R}_2} $$
SU
2
L
2
/
R
2
can be broken down to the diagonal
SU
(2)
L
/
R
gauge symmetry via bifundamental Higgs fields. In such a way, we for the first time successfully constructed three-family supersymmetric Pati-Salam models from non-rigid D6-branes with extra
d
-stacks of D6-branes as visible sectors. Interestingly, by introducing extra stack of D6-branes to the standard supersymmetric Pati-Salam models, the number of filler brane reduces in general, and eventually the models without any
USp
(
N
) gauge symmetry present. This reduces the exotic particles from filler brane intersection yet provides more vector-like particles from
$$ \mathcal{N} $$
N
= 2 subsector that are useful in renormalization group equation evolution as an advantage. Moreover, interesting degeneracy behavior with the same gauge coupling ratio exists in certain class of models.