Quantum coherent spin-electric control in a molecular nanomagnet at clock transitions
Quantum coherent spin-electric control in a molecular nanomagnet at clock transitions
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DOI：
10.1038/s41567-021-01355-4
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发表时间：
2021-10-14
期刊：
影响因子：
19.6
通讯作者：
Ardavan, Arzhang
中科院分区：
文献类型：
--
作者：
Liu, Junjie;Mrozek, Jakub;Ardavan, Arzhang
在纳米尺度上对自旋的电控制在自旋电子学中提供了显著的架构优势，因为电场可以被限制在比磁场更短的长度尺度上（1-5）。因此，最近在分子自旋材料（6-8）电场灵敏度的演示是诱人的，提高了宏观磁电器件（9-15）的量子类似物的可行性。然而，到目前为止报道的电场灵敏度相当弱，引发了如何设计具有更强自旋-电耦合的分子的问题。在这里，我们表明，一个路径是确定一个能量尺度的自旋谱，这是与结构的自由度与大量的电极化。我们研究了一个分子纳米磁体的例子，在这个例子中，一个小的结构畸变在自旋谱中建立了时钟跃迁（也就是说，其能量独立于磁场的一阶跃迁）;这种畸变与电偶极子有关的事实使我们能够将时钟跃迁能量控制到前所未有的程度。我们展示了量子自旋态的相干电控制，并利用它来独立地操纵晶体晶胞中的两个磁性相同但反转相关的分子。我们的发现为分子自旋在量子技术和自旋电子学中的应用铺平了道路。
Electrical control of spins at the nanoscale offers significant architectural advantages in spintronics, because electric fields can be confined over shorter length scales than magnetic fields(1-5). Thus, recent demonstrations of electric-field sensitivities in molecular spin materials(6-8) are tantalizing, raising the viability of the quantum analogues of macroscopic magneto-electric devices(9-15). However, the electric-field sensitivities reported so far are rather weak, prompting the question of how to design molecules with stronger spin-electric couplings. Here we show that one path is to identify an energy scale in the spin spectrum that is associated with a structural degree of freedom with a substantial electrical polarizability. We study an example of a molecular nanomagnet in which a small structural distortion establishes clock transitions (that is, transitions whose energy is to first order independent of the magnetic field) in the spin spectrum; the fact that this distortion is associated with an electric dipole allows us to control the clock-transition energy to an unprecedented degree. We demonstrate coherent electrical control of the quantum spin state and exploit it to independently manipulate the two magnetically identical but inversion-related molecules in the unit cell of the crystal. Our findings pave the way for the use of molecular spins in quantum technologies and spintronics.