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We perform quantum logic spectroscopy with a 27Al+/40Ca+ mixed ion crystal in a linear Paul trap for a measurement of the intercombination transition in 27Al+. Towards this end, Ramsey spectroscopy is used for probing the transition in 27Al+ and the clock transition in 40Ca+ in interleaved measurements. By using the precisely measured frequency of the clock transition in 40Ca+ as a frequency reference, we determine the frequency of the intercombination line to be = 1 122 842 857 334 736 (85) Hz and the Landé g-factor of the excited state to be = 0.428 133(2). [ABSTRACT FROM AUTHOR]

Fast entangling quantum gates can significantly enhance the performance of a trapped-ion quantum computer. In pursuit of implementing a fast two-qubit gate, we investigate the coherent excitation of a 40Ca+ ion with a train of picosecond pulses resonant to the 4S1/2 4P3/2 transition. The optical pulse train is derived from a mode-locked, stabilized optical frequency comb. We implement two techniques to characterize the pulse-ion interaction and show how all requirements can be met for an implementation of a fast phase gate operation. [ABSTRACT FROM AUTHOR]

We propose an experimental method to fully characterize the energy exchange of particles during the physical vapor deposition (PVD) process of thin surface layers. Our approach is based on the careful observation of perturbations of the oscillation frequency of a quartz crystal μ-balance induced by the particles’ interaction. With this technique it is possible to measure the momentum exchange of the atoms during the evaporation process and determine the ideal evaporation rate for uniform energy distribution. We are able to follow the desorption dynamics of particles’ immediately after the first layers have been formed. These results are in close relation to the surface binding energy of the evaporated material and offer a better control to obtain the desired properties of the thin surface layer. The novelty of our work consists of the demonstration that quartz crystal μ-balance can be successfully implemented to monitor complex dynamics through the energy interaction of particles during PVD. We applied our technique to investigate the PVD mechanism for diverse elements, usually implemented in the development of film surface layers, such as Cu, W, Au, Gd and In, and confirm that our results are in agreement with measurements done previously with other techniques such as low temperature photo-luminescence. [ABSTRACT FROM AUTHOR]