How to realize a universal quantum gate with trapped ions

Abstract

We report the realization of an elementary quantum processor based on a linear crystal of trapped ions. Each ion serves as a quantum bit (qubit) to store the quantum information in long lived electronic states. We present the realization of single-qubit and of universal two-qubit logic gates. The qwo-qubit operation relies on the coupling of the ions through their collective quantized motion. A detailed description of the setup and the methods is included.Comment: More detailed information as compared to Schmidt-Kaler et al., nature 422,408 (2003

Optimization of segmented linear Paul traps and transport of stored particles

“…The Aarhus hexapole design with endcaps [37] and the Innsbruck blade design [38] show a traditional macroscopic approach of mmsize linear trap design without segmentation of the control electrodes. The Michigan trap designs, the microstructured three-layer trap [39] and the semiconductor two-layer trap [40], represent the progress in the miniaturization of linear ion traps and the segmentation of the control electrodes for the transport of single ions and the splitting of ion crystals.…”

Scalable multiparticle entanglement of trapped ions

“…The generation of such W-states is performed in an ion-trap quantum processor 14 . We trap state with a series of laser pulses, the quantum state is read out with a CCD camera.…”

Absolute Frequency Measurement of theCa+404s S1/2Chwalla1, Benhelm2, Kim3 et al. 2009Phys. Rev. Lett.Self Cite16151240View full textAdd to dashboardCite

“…2. We use a linear Paul trap [14] with four blades separated by 2 mm and two tips of 5 mm separation providing radial and axial confinement. Applying a radiofrequency (RF) power of 9 W to the trap and setting the tips to a potential of 1000 V, we achieve typical secular trap frequencies ω r /2π=3.9 MHz in the radial and ω a /2π=1.2 MHz in the axial direction.…”

“…Since the linear Zeeman shift, the electric quadrupole shift as well as the AC-Zeeman shift caused by imbalanced currents in the trap electrodes cancel by the chosen measurement scheme, the largest remaining shift is due to the second order Zeeman effect which we determined to be 1.368(1) Hz at a mean magnetic field of 3.087(2) G. There was also a residual magnetic field drift which on average was 2(1)·10 −8 G/s. This lead to a measurement offset of 28 (14) mHz because this effect is not completely canceled by averaging over the six transitions without changing their order.…”