Miniaturization of conventional field effect transistors (FETs) approaches the fundamental limits beyond which opening and closing the transistor channel require higher gate voltage swing and cause higher power dissipation and heating. This problem could be eliminated by placing a ferroelectric layer between the FET gate electrode and the channel, which effectively amplifies the gate voltage. The original idea of using a bulk ferroelectric negative capacitor suffers however from irreversible multi-domain ferroelectric switching, which does not allow us to stabilize static negative capacitance, while a recent reversible solution with super-lattices may be difficult to integrate onto FET. Here, we introduce a solution which provides static negative capacitance from a nano-domain nucleus. Phase-field simulations confirm the robustness of this concept, the conveniently achievable small effective negative capacitance and the potentially high compatibility of such a negative nano-capacitor with FET technology.