Yumnam George, Chen Yiyao, Guo Jiasen, Keum Jong, Lauter Valeria, Singh Deepak Kumar
Department of Physics and Astronomy University of Missouri Columbia MO 65211 USA.
Oak Ridge National Laboratory Oak Ridge TN 37831 USA.
Adv Sci (Weinh). 2021 Feb 5;8(6):2004103. doi: 10.1002/advs.202004103. eCollection 2021 Mar.
A quantum magnetic state due to magnetic charges is never observed, even though they are treated as quantum mechanical variables in theoretical calculations. Here, the occurrence of a novel quantum disordered state of magnetic charges in a nanoengineered magnetic honeycomb lattice of ultra-small connecting elements is demonstrated. The experimental research, performed using spin resolved neutron scattering, reveals a massively degenerate ground state, comprised of low integer and energetically forbidden high integer magnetic charges, that manifests cooperative paramagnetism at low temperature. The system tends to preserve the degenerate configuration even under large magnetic field application. It exemplifies the robustness of disordered correlation of magnetic charges in a 2D honeycomb lattice. The realization of quantum disordered ground state elucidates the dominance of exchange energy, which is enabled due to the nanoscopic magnetic element size in nanoengineered honeycomb. Consequently, an archetypal platform is envisaged to study quantum mechanical phenomena due to emergent magnetic charges.
尽管磁荷在理论计算中被视为量子力学变量，但从未观测到由磁荷导致的量子磁态。在此，展示了在由超小连接元件构成的纳米工程磁性蜂窝晶格中出现的一种新型磁荷量子无序态。利用自旋分辨中子散射进行的实验研究揭示了一个高度简并的基态，它由低整数磁荷和能量上禁戒的高整数磁荷组成，在低温下表现出协同顺磁性。即使在施加强磁场的情况下，该系统仍倾向于保持简并构型。它例证了二维蜂窝晶格中磁荷无序关联的稳健性。量子无序基态的实现阐明了交换能的主导作用，这是由于纳米工程蜂窝中纳米级磁性元件的尺寸所促成的。因此，设想了一个原型平台来研究由涌现磁荷导致的量子力学现象。
