Physical Review Research (Sep 2023)
Optical stimulated-Raman sideband spectroscopy of a single ^{9}Be^{+} ion in a Penning trap
Abstract
We demonstrate optical sideband spectroscopy of a single ^{9}Be^{+} ion in a cryogenic 5 tesla Penning trap using two-photon stimulated-Raman transitions between the two Zeeman sublevels of the 1s^{2}2s ground state manifold. By applying two complementary coupling schemes, we accurately measure Raman resonances with and without contributions from motional sidebands. From the latter we obtain an axial sideband spectrum with an effective mode temperature of (3.1±0.4) mK. These results are a key step for quantum logic operations in Penning traps, applicable to high-precision matter-antimatter comparison tests in the baryonic sector of the standard model.