Phosphorus donor impurities in silicon are a promising candidate for solid-state quantum computing due to their exceptionally long coherence times and high fidelities. However, individual addressability of exchange coupled donors with separations ~15 nm is challenging. We show that by using atomic precision lithography, we can place a single P donor next to a 2P molecule 16 ± 1 nm apart and use their distinctive hyperfine coupling strengths to address qubits at vastly different resonance frequencies. In particular, the single donor yields two hyperfine peaks separated by 97 ± 2.5 MHz, in contrast to the donor molecule that exhibits three peaks separated by 262 ± 10 MHz. Atomistic tight-binding simulations confirm the large hyperfine interaction strength in the 2P molecule with an interdonor separation of ~0.7 nm, consistent with lithographic scanning tunneling microscopy images of the 2P site during device fabrication. We discuss the viability of using donor molecules for built-in addressability of electron spin qubits in silicon.

中文翻译：

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使用硅中的供体和供体分子进行可寻址电子自旋共振。


硅中的磷供体杂质由于其极长的相干时间和高保真度而成为固态量子计算的有希望的候选者。然而，分离度约为 15 nm 的交换耦合供体的个体可寻址性具有挑战性。我们证明，通过使用原子精密光刻，我们可以将单个 P 供体放置在相距 16 ± 1 nm 的 2P 分子旁边，并利用其独特的超精细耦合强度来处理截然不同的共振频率下的量子位。特别是，单一供体产生两个相距 97 ± 2.5 MHz 的超精细峰，而供体分子则产生三个相距 262 ± 10 MHz 的峰。原子紧结合模拟证实了 2P 分子中的大超精细相互作用强度，供体间间距约为 0.7 nm，与器件制造过程中 2P 位点的光刻扫描隧道显微镜图像一致。我们讨论了使用供体分子实现硅中电子自旋量子位的内置可寻址性的可行性。