Fataftah Majed S, Krzyaniak Matthew D, Vlaisavljevich Bess, Wasielewski Michael R, Zadrozny Joseph M, Freedman Danna E
Department of Chemistry , Northwestern University , Evanston , IL 60208 , USA . Email:
The Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , IL 60208 , USA.
Chem Sci. 2019 May 31;10(27):6707-6714. doi: 10.1039/c9sc00074g. eCollection 2019 Jul 21.
Harnessing synthetic chemistry to design electronic spin-based qubits, the smallest unit of a quantum information system, enables us to probe fundamental questions regarding spin relaxation dynamics. We sought to probe the influence of metal-ligand covalency on spin-lattice relaxation, which comprises the upper limit of coherence time. Specifically, we studied the impact of the first coordination sphere on spin-lattice relaxation through a series of four molecules featuring V-S, V-Se, Cu-S, and Cu-Se bonds, the PhP salts of the complexes [V(CHS)] (), [Cu(CHS)] (), [V(CHSe)] (), and [Cu(CHSe)] (). The combined results of pulse electron paramagnetic resonance spectroscopy and ac magnetic susceptibility studies demonstrate the influence of greater M-L covalency, and consequently spin-delocalization onto the ligand, on elongating spin-lattice relaxation times. Notably, we observe the longest spin-lattice relaxation times in , and spin echos that survive until room temperature in both copper complexes ( and ).
利用合成化学设计基于电子自旋的量子比特（量子信息系统的最小单元），使我们能够探究有关自旋弛豫动力学的基本问题。我们试图探究金属 - 配体共价性对自旋 - 晶格弛豫的影响，自旋 - 晶格弛豫构成了相干时间的上限。具体而言，我们通过一系列具有V - S、V - Se、Cu - S和Cu - Se键的四个分子，即配合物[V(CHS)]（）、[Cu(CHS)]（）、[V(CHSe)]（）和[Cu(CHSe)]（）的PhP盐，研究了第一配位层对自旋 - 晶格弛豫的影响。脉冲电子顺磁共振光谱和交流磁化率研究的综合结果表明，更大的M - L共价性以及由此导致的自旋离域到配体上，对延长自旋 - 晶格弛豫时间有影响。值得注意的是，我们在 中观察到最长的自旋 - 晶格弛豫时间，并且在两种铜配合物（ 和 ）中观察到自旋回波一直持续到室温。
