Lohmann Sven-Hendrik, Trerayapiwat Kasidet Jing, Niklas Jens, Poluektov Oleg G, Sharifzadeh Sahar, Ma Xuedan
Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States.
Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States.
ACS Nano. 2020 Dec 22;14(12):17675-17682. doi: 10.1021/acsnano.0c08782. Epub 2020 Dec 11.
Chemical functionalization-introduced quantum defects in single-walled carbon nanotubes (SWCNTs) have shown compelling optical properties for their potential applications in quantum information science and bioimaging. Here, we utilize temperature- and power-dependent electron spin resonance measurements to study the fundamental spin properties of SWCNTs functionalized with well-controlled densities of quantum defects. Signatures of isolated spins that are highly localized at the defect sites are observed, which we further confirm with density functional theory calculations. Applying temperature-dependent line width analysis and power-saturation measurements, we estimate the spin-lattice relaxation time and spin dephasing time to be around 9 μs and 40 ns, respectively. These findings of the localized spin states that are associated with the quantum defects not only deepen our understanding of the molecular structures of the quantum defects but could also have strong implications for their applications in quantum information science.
化学功能化引入的单壁碳纳米管（SWCNT）中的量子缺陷，因其在量子信息科学和生物成像中的潜在应用而展现出引人注目的光学特性。在此，我们利用依赖于温度和功率的电子自旋共振测量，来研究具有精确控制的量子缺陷密度的功能化SWCNT的基本自旋特性。观察到高度局域在缺陷位点的孤立自旋的特征，我们通过密度泛函理论计算进一步证实了这一点。应用依赖于温度的线宽分析和功率饱和测量，我们估计自旋-晶格弛豫时间和自旋退相时间分别约为9 μs和40 ns。这些与量子缺陷相关的局域自旋态的发现，不仅加深了我们对量子缺陷分子结构的理解，而且对它们在量子信息科学中的应用可能具有重要意义。
