Jelezko F, Gaebel T, Popa I, Gruber A, Wrachtrup J
3. Physikalisches Institut, Universität Stuttgart, Stuttgart, Germany.
Phys Rev Lett. 2004 Feb 20;92(7):076401. doi: 10.1103/PhysRevLett.92.076401.
Rabi nutations and Hahn echo modulation of a single electron spin in a single defect center have been observed. The coherent evolution of the spin quantum state is followed via optical detection of the spin state. Coherence times up to several microseconds at room temperature have been measured. Optical excitation of the spin states leads to decoherence. Quantum beats between electron spin transitions in a single spin Hahn echo experiment are observed. A closer analysis reveals that beats also result from the hyperfine coupling of the electron spin to a single 14N nuclear spin. The results are analyzed in terms of a density matrix approach of an electron spin interacting with two oscillating fields.
已观察到单个缺陷中心中单个电子自旋的拉比振荡和哈恩回波调制。通过对自旋态的光学检测来跟踪自旋量子态的相干演化。在室温下测量到相干时间长达数微秒。自旋态的光激发会导致退相干。在单个自旋哈恩回波实验中观察到电子自旋跃迁之间的量子拍。进一步分析表明，拍频也是由电子自旋与单个14N核自旋的超精细耦合引起的。根据电子自旋与两个振荡场相互作用的密度矩阵方法对结果进行了分析。
