SUSY double-well matrix model as 2D IIA superstring on RR background

We discuss an interpretation of a simple supersymmetric matrix model with a double-well potential as two-dimensional type IIA superstrings on a nontrivial Ramond-Ramond background. In particular, we can see direct correspondence between single trace operators in the matrix model and vertex operators in the type IIA theory by computing scattering amplitudes and comparing the results in both sides. Next, we explicitly compute nonperturbative instanton contributions in the matrix model and find that they survive in a double scaling limit realizing the type IIA superstring theory. This suggests that the supersymmetry is spontaneously broken by nonperturbative effect in the target space of the type IIA superstring theory.