Radiative Kähler moduli stabilization

We propose a new type of Kähler moduli stabilization mechanisms in type IIB superstring theory on Calabi-Yau manifolds with the positive Euler number. The overall Kähler modulus can be perturbatively stabilized by radiative corrections due to sparticles. Its minimum is the anti-de Sitter vacuum, where supersymmetry is broken. We can uplift it to the de Sitter vacuum by introducing anti-D-branes, keeping the modulus stabilized. Although our numerical results depend on the choice of the cutoff scale and degeneracies of sparticles, at any rate there exist the parameter spaces where the masses of Kaluza-Klein and stringy modes are larger than the cutoff scale. Furthermore, this stabilization scenario predicts an ultralight axion.

Figure 1

The scalar potential (17) as functions of CY volume $\mathcal{V}$ and noncanonically normalized modulus $\tau$, where the CY volume is approximated as $\mathcal{V}=(T+\overline{T}{)}^{3/2}$ with $T=\tau +i\sigma$ in the right panel.

Figure 2

The scalar potential in units of $\mathrm{\Lambda }=m_{\mathrm{KK}}$ as functions of CY volume $\mathcal{V}$ and noncanonically normalized modulus $\tau$, where the CY volume is approximated as $\mathcal{V}=(T+\overline{T}{)}^{3/2}$ with $T=\tau +i\sigma$ in the right panel.