Gaebler J P, Tan T R, Lin Y, Wan Y, Bowler R, Keith A C, Glancy S, Coakley K, Knill E, Leibfried D, Wineland D J
National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA.
Phys Rev Lett. 2016 Aug 5;117(6):060505. doi: 10.1103/PhysRevLett.117.060505. Epub 2016 Aug 4.
We report high-fidelity laser-beam-induced quantum logic gates on magnetic-field-insensitive qubits comprised of hyperfine states in ^{9}Be^{+} ions with a memory coherence time of more than 1 s. We demonstrate single-qubit gates with an error per gate of 3.8(1)×10^{-5}. By creating a Bell state with a deterministic two-qubit gate, we deduce a gate error of 8(4)×10^{-4}. We characterize the errors in our implementation and discuss methods to further reduce imperfections towards values that are compatible with fault-tolerant processing at realistic overhead.
我们报告了在由(^{9}Be^{+})离子的超精细态组成的对磁场不敏感的量子比特上实现的高保真激光束诱导量子逻辑门,其存储相干时间超过1秒。我们展示了单比特门,每个门的错误率为3.8(1)×10(^{-5})。通过使用确定性双比特门创建贝尔态,我们推断出门错误率为8(4)×10(^{-4})。我们对实现中的错误进行了表征,并讨论了进一步降低缺陷以达到与实际开销下的容错处理兼容的值的方法。