We consider a narrow magneto-dipole transition in the ${}^{169}\text{Tm}$ atom at the wavelength of $1.14 \mu \mathrm{m}$ as a candidate for a two-dimensional-optical lattice clock. Calculating dynamic polarizabilities of the two clock levels $\left[\text{Xe}\right]4f^{13}6s^2(J=7/2)$ and $\left[\text{Xe}\right]4f^{13}6s^2(J=5/2)$ in the spectral range from 250 to 1200 nm, we find a “magic” wavelength for the optical lattice at 807 nm. Frequency shifts due to black-body radiation (BBR), the van der Waals interaction, the magnetic dipole-dipole interaction, and other effects which can perturb the transition frequency are calculated. The transition at $1.14 \mu \mathrm{m}$ demonstrates low sensitivity to the BBR shift corresponding to $8\times {10}^{-17}$ in fractional units at room temperature which makes it an interesting candidate for high-performance optical clocks. The total estimated frequency uncertainty is less than $5\times {10}^{-18}$ in fractional units. By direct excitation of the $1.14 \mu \mathrm{m}$ transition in Tm atoms loaded into an optical dipole trap, we set the lower limit for the lifetime of the upper clock level $\left[\text{Xe}\right]4f^{13}6s^2(J=5/2)$ of 112 ms which corresponds to a natural spectral linewidth narrower than 1.4 Hz. The polarizability of the Tm ground state was measured by the excitation of parametric resonances in the optical dipole trap at 532 nm.

• Received 9 June 2016

DOI:https://doi.org/10.1103/PhysRevA.94.022512