【量子革命】RF不要で核スピン制御、量子コンピュータの常識が崩れる

Описание: 論文情報
・url: http://arxiv.org/html/2601.21499v1
・title: RF-free driving of nuclear spins with color centers in silicon carbide
・abstract: Color centers that enable nuclear-spin control without RF fields offer a powerful route towards simplified and scalable quantum devices. Such capabilities are especially valuable for quantum sensing and computing platforms that already find applications in biology, materials science, and geophysics. A key challenge is the coherent manipulation of nearby nuclear spins, which serve as quantum memories and auxiliary qubits but conventionally require additional high-power RF fields which increase the experimental complexity and overall power consumption. Finding systems where both electron and nuclear spins can be controlled using a single MW source is therefore highly desirable. Here, using a modified divacancy center in silicon carbide, we show that coherent control of a coupled nuclear spin is possible without any RF fields. Instead, MW pulses driving the electron spin also manipulate the nuclear spin through hyperfineenhanced effects, activated by a precisely tilted external magnetic field. We demonstrate high-fidelity nuclear-spin control, achieving 89% two-qubit tomography fidelity and nearly T1-limited nuclear coherence times. This approach offers a simplified and scalable route for future quantum applications.
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従来の量子デバイスに不可欠だった高出力RF信号を完全に排除する画期的技術が登場。シリコンカーバイドの特殊な欠陥構造を使い、磁場をわずか2度傾けるだけで核スピンを制御。装置の簡素化と低消費電力化により、量子技術が研究室から実社会へ。スマホサイズの量子センサーや盗聴不可能な通信インフラが、もう目の前まで来ています。