44 research outputs found
Quantum control of Sr in a miniature linear Paul trap
We report on the construction and characterization of an apparatus for
quantum information experiments using Sr ions. A miniature linear
radio-frequency (rf) Paul trap was designed and built. Trap frequencies above 1
MHz in all directions are obtained with 50 V on the trap end-caps and less than
1 W of rf power. We encode a quantum bit (qubit) in the two spin states of the
electronic ground-state of the ion. We constructed all the necessary
laser sources for laser cooling and full coherent manipulation of the ions'
external and internal states. Oscillating magnetic fields are used for coherent
spin rotations. High-fidelity readout as well as a coherence time of 2.5 ms are
demonstrated. Following resolved sideband cooling the average axial vibrational
quanta of a single trapped ion is and a heating rate of
ms is measured.Comment: 8 pages,9 figure
Microfabricated Ion Traps
Ion traps offer the opportunity to study fundamental quantum systems with
high level of accuracy highly decoupled from the environment. Individual atomic
ions can be controlled and manipulated with electric fields, cooled to the
ground state of motion with laser cooling and coherently manipulated using
optical and microwave radiation. Microfabricated ion traps hold the advantage
of allowing for smaller trap dimensions and better scalability towards large
ion trap arrays also making them a vital ingredient for next generation quantum
technologies. Here we provide an introduction into the principles and operation
of microfabricated ion traps. We show an overview of material and electrical
considerations which are vital for the design of such trap structures. We
provide guidance in how to choose the appropriate fabrication design, consider
different methods for the fabrication of microfabricated ion traps and discuss
previously realized structures. We also discuss the phenomenon of anomalous
heating of ions within ion traps, which becomes an important factor in the
miniaturization of ion traps
Optical-clock local-oscillator stabilization scheme
Stabilization of a laser to an optical-clock transition has been demonstrated using Ramsey's phase-modulation technique. The technique was implemented using a 674 nm laser and a component of the 5 s S-2(1/2) -> 4d D-2(5/2) optical clock transition in a single Sr-88(+) ion. The lock performance observed was consistent with the short-term stability of the local oscillator. Compared with existing frequency-modulation stabilization schemes, this technique offers advantages for use in single-ion optical clocks through its possible increased resolution and the ability to conveniently compensate known systematic shifts. (c) 2006 Optical Society of America