Joint Quantum Institute, University of Maryland Department of Physics and National Institute of Standards and Technology, College Park, Maryland 20742 USA.
Phys Rev Lett. 2010 Aug 27;105(9):090502. doi: 10.1103/PhysRevLett.105.090502. Epub 2010 Aug 26.
We demonstrate single-qubit operations on a trapped atom hyperfine qubit using a single ultrafast pulse from a mode-locked laser. We shape the pulse from the laser and perform a π rotation of the qubit in less than 50 ps with a population transfer exceeding 99% and negligible effects from spontaneous emission or ac Stark shifts. The gate time is significantly shorter than the period of atomic motion in the trap (Ω(Rabi)/ν(trap)>10(4)), demonstrating that this interaction takes place deep within the strong excitation regime.
我们使用锁模激光的单个超快脉冲在被俘原子的超精细量子比特上演示了单量子比特操作。我们对激光脉冲进行整形，并在不到 50 ps 的时间内完成了量子比特的π旋转，其中超过 99%的粒子发生了转移，自发辐射或交流斯塔克频移的影响可以忽略不计。门控时间明显短于阱中原子运动的周期（Ω（拉比）/ν（阱）>10（4）），这表明这种相互作用发生在强激发态的深部。
