Versatile laser-free trapped-ion entangling gates
POSTER
Abstract
We present a general theory for laser-free entangling gates with trapped-ion hyperfine qubits, using either static or oscillating magnetic-field gradients combined with a pair of uniform microwave fields symmetrically detuned about the qubit frequency. By transforming into a `bichromatic' interaction picture, we show that either ${\hat{\sigma}_{\phi}\otimes\hat{\sigma}_{\phi}}$ or ${\hat{\sigma}_{z}\otimes\hat{\sigma}_{z}}$ geometric phase gates can be performed. The gate operation is determined by selecting the microwave detuning. The driving parameters can be tuned to provide \textit{intrinsic dynamical decoupling} from qubit frequency fluctuations. The ${\hat{\sigma}_{z}\otimes\hat{\sigma}_{z}}$ gates can be implemented in a novel manner which eases experimental constraints. We also discuss novel gate techniques that are insensitive to heating.
*R.S., S.C.B., and D.T.C.A. are Associates in the Professional Research Experience Program (PREP) operated jointly by NIST and the University of Colorado Boulder under award 70NANB18H006 from the U.S. Department of Commerce, National Institute of Standards and Technology. This work was supported by ONR, and the NIST Quantum Information Program. Part of this work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.