School of Physics and Centre of Excellence for Quantum Computation and Communication Technology, UNSW Australia , Sydney, New South Wales 2052, Australia.
ACS Nano. 2017 Mar 28;11(3):2444-2451. doi: 10.1021/acsnano.6b06362. Epub 2016 Nov 17.
The ability to apply gigahertz frequencies to control the quantum state of a single P atom is an essential requirement for the fast gate pulsing needed for qubit control in donor-based silicon quantum computation. Here, we demonstrate this with nanosecond accuracy in an all epitaxial single atom transistor by applying excitation signals at frequencies up to ≈13 GHz to heavily phosphorus-doped silicon leads. These measurements allow the differentiation between the excited states of the single atom and the density of states in the one-dimensional leads. Our pulse spectroscopy experiments confirm the presence of an excited state at an energy ≈9 meV, consistent with the first excited state of a single P donor in silicon. The relaxation rate of this first excited state to the ground state is estimated to be larger than 2.5 GHz, consistent with theoretical predictions. These results represent a systematic investigation of how an atomically precise single atom transistor device behaves under radio frequency excitations.
将千兆赫兹频率应用于控制单个 P 原子的量子态，是在基于供体的硅量子计算中实现量子比特控制所需的快速门脉冲所必需的。在这里，我们通过在高达 ≈13 GHz 的频率下向重掺杂磷的硅引线施加激励信号，在全外延单原子晶体管中以纳秒级精度证明了这一点。这些测量允许区分单个原子的激发态和一维引线中的态密度。我们的脉冲光谱实验证实了在 ≈9 meV 的能量处存在激发态，与硅中单个 P 供体的第一激发态一致。该第一激发态到基态的弛豫率估计大于 2.5 GHz，与理论预测一致。这些结果代表了对原子精度的单原子晶体管器件在射频激发下的行为的系统研究。
