Wineland, D.J.Itano, Wayne M.Bergquist, J.C.Hulet, Randall G.2015-03-302015-03-301987Wineland, D.J., Itano, Wayne M., Bergquist, J.C., et al.. "Laser-cooling limits and single-ion spectroscopy." <i>Physical Review A,</i> 36, no. 5 (1987) American Physical Society: 2220-2232. http://dx.doi.org/10.1103/PhysRevA.36.2220.https://hdl.handle.net/1911/79405The limitations to the achievement of low kinetic energies for laser cooling of single ions confined in electromagnetic traps are discussed. Sideband cooling of an ion in an rf (Paul) trap is reexamined including the effects of finite laser bandwidth and the energy of the rf micromotion. The micromotion is the oscillatory motion of the ion at the same frequency as the rf voltage applied to the trap electrodes. Sideband cooling of ions in a Penning trap is examined for the first time. In both cases, cooling to the zero-point energy of the ion in the trap should be possible and a method for verifying this condition is suggested. The implications for high-resolution, high-accuracy spectroscopy are investigated. Under certain conditions, the uncertainty in the second-order Doppler shift may be significantly less than 1 part in 10?18.engArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.Journal articlehttp://dx.doi.org/10.1103/PhysRevA.36.2220