Laser cooling of a stored ion beam to 1 mK

Theory of tapered laser cooling

“…At present, there exist only two storage rings in the world where laser cooling system has been installed; namely, the TSR ring [5] at MPI, Heidelberg, and the ASTRID ring [6] at Aarhus University, Denmark. However, these storage rings do not satisfy the necessary condition of crystal maintenance although with minor modifcations they would.…”

Three-Dimensional Laser Cooling of Stored and Circulating Ion Beams by Means of a Coupling Cavity

“…Longitudinal temperatures in the mK range have been achieved with a beam of 100 keV 7Li+ ions [3]. The transverse temperature is, however, on the order of 1000 K. To date, no effective method has been developed to realize simultaneous cooling in both the longitudinal and transverse directions, although a possible transverse cooling method was suggested some time ago [4].…”

“…Laser cooling [1] of stored, circulating ion beams is remarkably effective [2,3]. Longitudinal temperatures in the mK range have been achieved with a beam of 100 keV 7Li+ ions [3].…”

“…The transverse electric field is zero, but there are transverse magnetic fields. These electromagnetic fields are derivable from the vector potential (2) In addition, we also have an rf bunching cavity whose vector potential is (3) where Vb and Olb are, respectively, the voltage amplitude and angular frequency of the bunching cavity, and <!>b is the initial rf phase.…”

“…Taking the distance s along tIle reference particle orbit in a storage ring as L~e independent variable, instead of time, and considering only dipole and quadrupole magnets installed on the ring, we obtain, together with the vector potentials in Eqs. (2) and (3), the approximate Hamiltonian…”