  The Kitaev model is a remarkable spin model with gapped and gapless spin
liquid phases, which are potentially realized in iridates and
$\alpha$-RuCl$_3$. In the recent experiment of $\alpha$-RuCl$_3$, the signature
of a nematic transition to the gapped toric code phase, which breaks the $C_3$
symmetry of the system, has been observed through the angle dependence of the
heat capacity. We here propose a mechanism by which the nematic transition can
be detected electrically. This is seemingly impossible because
$J_\textrm{eff}=1/2$ spins do not have an electric quadrupole moment (EQM).
However, in the second-order perturbation the virtual state with a nonzero EQM
appears, which makes the nematic order parameter detectable by nuclear magnetic
resonance and M\"ossbauer spectroscopy. The purely magnetic origin of EQM is
different from conventional electronic nematic phases, allowing the direct
detection of the realization of Kitaev's toric error-correction code.
