Neukelmance B, Hue B, Schaeverbeke Q, Jarjat L, Théry A, Craquelin J, Legrand W, Cubaynes T, Abulizi G, Becdelievre J, El Abbassi M, Larrouy A, Ourak K F, Stefani D, Sulpizio J A, Cottet A, Desjardins M M, Kontos T, Delbecq M R
Laboratoire de Physique de l'École normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, Paris, France.
C12 Quantum Electronics, Paris, France.
Nat Commun. 2025 Jul 1;16(1):5636. doi: 10.1038/s41467-025-60952-6.
Semiconductor quantum dots are an attractive platform for the realisation of quantum processors. To achieve long-range coupling between them, quantum dots have been integrated into microwave cavities. However, it has been shown that their coherence is then reduced compared to their cavity-free implementations. Here, we manipulate the quantum states of a suspended carbon nanotube double quantum dot with ferromagnetic contacts embedded in a microwave cavity. By performing quantum manipulations via the cavity photons, we demonstrate coherence times of the order of 1.3 μs, two orders of magnitude larger than those measured so far in any carbon quantum circuit and one order of magnitude larger than silicon-based quantum dots in comparable environment. This holds promise for carbon as a host material for spin qubits in circuit quantum electrodynamics.
半导体量子点是实现量子处理器的一个有吸引力的平台。为了实现它们之间的长程耦合，量子点已被集成到微波腔中。然而，已经表明，与无腔实现相比，它们的相干性会降低。在这里，我们通过嵌入在微波腔中的铁磁接触来操纵悬浮碳纳米管双量子点的量子态。通过经由腔光子执行量子操纵，我们展示了约1.3微秒量级的相干时间，比迄今为止在任何碳量子电路中测量到的相干时间大两个数量级，并且比在可比环境中的硅基量子点大一个数量级。这为碳作为电路量子电动力学中自旋量子比特的主体材料带来了希望。
