论文标题
量子磁铁CS $ _2 $ COCL $ _4 $中的量化和控制纠缠
Quantifying and controlling entanglement in the quantum magnet Cs$_2$CoCl$_4$
论文作者
论文摘要
缺乏实验检测和量化量子物质纠缠的方法阻碍了我们识别托管高度纠缠相的材料（例如量子自旋液体）的能力。因此，我们研究了基于三个纠缠证人的纠缠实现模型独立的测量协议的可行性：一个纠缠见证人：一键，两键，两键和量子渔民信息（QFI）。我们对CS $ _2 $ COCL $ _4 $执行高分辨率INS测量值，这是$ s = 1/2 $横向场XXZ XXZ旋转链的紧密实现，我们可以在其中使用磁场控制纠缠，并将其与密度 - 矩阵重新统治组计算进行验证。这三位证人允许我们推断纠缠属性，并扣除材料中量子状态的扣除。我们发现QFI是纠缠的特别强大的实验探针，而单键和两键则需要更仔细的分析。我们的结果为量子自旋系统的一般纠缠检测方案奠定了基础。
The lack of methods to experimentally detect and quantify entanglement in quantum matter impedes our ability to identify materials hosting highly entangled phases, such as quantum spin liquids. We thus investigate the feasibility of using inelastic neutron scattering (INS) to implement a model-independent measurement protocol for entanglement based on three entanglement witnesses: one-tangle, two-tangle, and quantum Fisher information (QFI). We perform high-resolution INS measurements on Cs$_2$CoCl$_4$, a close realization of the $S=1/2$ transverse-field XXZ spin chain, where we can control entanglement using the magnetic field, and compare with density-matrix renormalization group calculations for validation. The three witnesses allow us to infer entanglement properties and make deductions about the quantum state in the material. We find QFI to be a particularly robust experimental probe of entanglement, whereas the one- and two-tangles require more careful analysis. Our results lay the foundation for a general entanglement detection protocol for quantum spin systems.
