  Long ground-Rydberg coherence lifetime is interesting for implementing
high-fidelity quantum logic gates, many-body physics, and other quantum
information protocols. However, the potential formed by a conventional
far-off-resonance red-detuned optical-dipole trap (ODT) is usually repulsive
for Rydberg atoms, which will result in fast atom loss and low repetition rate
of the experimental sequence. These issues can be addressed by a magic ODT. We
performed the calculation of ODT's magic detuning for confinement of cesium
ground state and Rydberg state with the same potential well. We used a
sum-over-states method to calculate the dynamic polarizabilities of $6S_{1/2}$
ground state and highly-excited ($nS_{1/2}$ and $nP_{3/2}$) Rydberg state of
cesium atoms, and identify corresponding magic detuning for optical wavelengths
in the range of $850 - 2000$ nm. We estimated the trapping lifetime of cesium
Rydberg atoms confined in the magic ODT by including different dissipative
mechanisms. Furthermore, we have experimentally realized an 1879.43-nm
single-frequency laser system with a watt-level output power for setting up the
magic ODT for $6S_{1/2}$ ground-state and $84P_{3/2}$ Rydberg-state cesium cold
atoms.

Atomic Physics