Inverse seesaw in supersymmetry

We study a mechanism where tiny neutrino masses arise only from radiative contribution in a supersymmetric model. In each generation, the tree-level light neutrino mass is rotated away by introducing a second SM singlet $s_L$ that forms a Dirac mass term with the right-handed neutrino $n_R$. Even with non-zero Majorana neutrino mass for the right-handed neutrinos $M_{R} \bar{n^{c}{R}} n{R}$, the lightest neutrino remains massless at tree level due to an approximate symmetry as $U(1{)}_{\nu -s}$. Holomorphic feature of superpotential ensures that the Majorana neutrino masses $M_{R} \bar{n^{c}{R}} n{R}$and$M^{*}{R} \bar{s^{c}{L}} s_{L}$ are not generated simultaneously. However, the $U(1{)}_{\nu -s}$ is not respected by the SM gauge interactions or interaction with Higgs. Consequently, tiny neutrino masses arise from radiative contributions. It is also shown that the right-handed neutrino Majorana mass $M_R$ can be at $\mathcal{O}$(KeV) to obtain the proper light neutrino mass.