论文标题
横向场Ising型号材料conb $ _2 $ o $ _6 $的单人离子属性
Single-ion properties of the transverse-field Ising model material CoNb$_2$O$_6$
论文作者
论文摘要
conb $ _2 $ o $ _6 $是为数不多的材料之一，该材料近似于其量子关键点附近的一维横向式iSing模型（1D-TFIM）。已经推断出，co $^{2+} $充当伪旋转1/2，具有各向异性交换相互作用，它们在很大程度上是类似的，从而实现了TFIM的实现。但是，已知CONB $ _2 $ o $ _6 $的行为与远离量子关键点的理想TFIM不同，这需要以微观依赖性（Kitaev）为单相关的术语，以微观的粘合物为小型PSEUDO-SPSEDO-SPSEDO-SPSEDO-SPSEDO-SPENDO-SPSEDO-SPEDO-SPERUDO-SPERUDO-SPERUDO-SPERUDO-SPERUDO-SPERUDO-SPERUDO-SPERUDO-SPERUDE-SPENDO。预计这些术语将部分由单离子物理学控制，即伪旋转1/2角动量双线的波函数。在这里，我们介绍了无弹性中子散射测量结果和conb $ _2 $ o $ $ _6 $的电子顺磁共振光谱，这阐明了CO $^{2+} $的单人离子物理学，conb $ _2 $ _2 $ o $ _6 $首次是首次。我们发现该系统由中间旋转轨道耦合的哈密顿量很好地描述，而基态是具有各向异性$ g $ -tensor的隔离良好的kramers doublet。我们提供了该双重双重的近似波形，我们期望这将在各向异性交换相互作用的理论研究中有用。
CoNb$_2$O$_6$ is one of the few materials that is known to approximate the one-dimensional transverse-field Ising model (1D-TFIM) near its quantum critical point. It has been inferred that Co$^{2+}$ acts as a pseudo-spin 1/2 with anisotropic exchange interactions that are largely Ising-like, enabling the realization of the TFIM. However, the behavior of CoNb$_2$O$_6$ is known to diverge from the ideal TFIM under transverse magnetic fields that are far from the quantum critical point, requiring the consideration of additional anisotropic, bond-dependent (Kitaev-like) terms in the microscopic pseudo-spin 1/2 Hamiltonian. These terms are expected to be controlled in part by single-ion physics, namely the wavefunction for the pseudo-spin 1/2 angular momentum doublet. Here, we present the results of both inelastic neutron scattering measurements and electron paramagnetic resonance spectroscopy on CoNb$_2$O$_6$, which elucidate the single-ion physics of Co$^{2+}$ in CoNb$_2$O$_6$ for the first time. We find that the system is well-described by an intermediate spin-orbit coupled Hamiltonian, and the ground state is a well-isolated Kramers doublet with an anisotropic $g$-tensor. We provide the approximate wavefunctions for this doublet, which we expect will be useful in theoretical investigations of the anisotropic exchange interactions.
