de Sitter vacuum from $R^2$ supergravity

We propose a supergravity model with a constrained curvature multiplet, which realizes the Starobinsky inflation and the de Sitter vacuum in the present Universe simultaneously. Surprisingly, at the vacuum, the soft supersymmetry-breaking scale for the minimal supersymmetric standard model sector becomes the TeV scale; however, the gravitino mass scale becomes much higher than that of soft supersymmetry breaking. Such a hierarchical structure, which naturally avoids the gravitino problem, appears without introducing a new scale other than the inflation scale.