New Limit on the Electron Electric Dipole Moment

Abstract

We present the result of our most recent search for $T$ violation in ${}^{205}\mathrm{Tl}$, which is interpreted in terms of an electric dipole moment of the electron $d_e$. We find $d_e=(6.9\pm 7.4)\times {10}^{-28\mathrm{}}e\mathrm{cm}$, which yields an upper limit $|d_e|\le 1.6\times {10}^{-27\mathrm{}}e\mathrm{cm}$ with $90\%$ confidence. The present apparatus is a major upgrade of the atomic beam magnetic-resonance device used to set the previous limit on $d_e$.