On K3-fibred LARGE Volume Scenario with de Sitter vacua from anti-D3-branes

Abstract

In the context of type IIB superstring compactifications on K3-fibred (weak) Swiss-cheese Calabi Yau (CY) orientifolds, we consider the realisation of de Sitter vacua obtained through the introduction of an overline{D3} -brane at the tip of a highly warped throat of Klebanov-Strassler type. Aiming to have a concrete global realisation, we perform a systematic search for the CY threefolds with 2 < h1,1< 5 arising from the Kreuzer-Skarke database, which satisfy the minimal requirements of being K3-fibred and suitable for moduli stabilisation within the LARGE Volume Scenario (LVS). In this context, after scanning the set of K3-fibred CY threefolds with a so-called diagonal del-Pezzo divisor needed for LVS, we realise that one of the main challenging requirements for having overline{D3} -brane uplifting is to find a suitable orientifold involution which can simultaneously result in a sufficient large D3 tadpole charge along with the presence of suitable O3-planes. In our detailed analysis (limited to) using the CY threefolds with small h1,1, we observe that these topological requirements rule out most of the CY geometries leading to only few possibly suitable candidates for the purpose of overline{D3} -brane uplifting. Subsequently, we present a global model using one such explicit K3-fibred CY threefold with h1,1 = 4 in which all the moduli can be consistently stabilised in a de Sitter minimum of the scalar potential.