EBS-enabled magnetic BCDI of domains in Sr2IrO4

Bragg coherent diffraction imaging (BCDI) uniquely enables the study of small crystalline samples with high strain sensitivity (~2 × 10−4) and high spatial resolution (~10 nm) in three-dimensions (3D). Here we propose to use BCDI to image magnetic domains within a single crystal of Sr2IrO4, a high-temperature superconductor (HTSC) analogue. We plan to image the (106) magnetic Bragg peak to observe the evolution of 3D antiferromagnetic (AFM) domains in real space, complemented by collecting normal charge (116) Bragg peaks below and above TN = 225K. The two peaks will provide information on how magnetic domains evolve as a function of temperature, and how they are pinned to any defects in the lattice or are confined by the crystal morphology. This experiment will study the evolution of 3D magnetic domains and domain walls to understand fundamental magnetic interactions that make iridates analogous to superconducting cuprates.

布拉格相干衍射成像（Bragg Coherent Diffraction Imaging, BCDI）具备独特优势，可在三维（3D）空间中以约2×10⁻⁴的高应变灵敏度和约10 nm的高空间分辨率对微小晶体样品开展研究。本文提出利用BCDI对高温超导体（HTSC）类似物Sr₂IrO₄单晶体内部的磁畴进行成像。我们计划通过采集（106）晶面的磁布拉格峰，观测实空间中三维反铁磁（AFM）畴的演化过程，并辅以在TN=225K上下采集常规电荷型（116）晶面布拉格峰的数据。两类布拉格峰将用于揭示磁畴随温度的演化规律，以及磁畴如何被晶格缺陷钉扎或受晶体形貌约束。本实验将研究三维磁畴及畴壁的演化过程，以期阐明使铱酸盐与超导铜酸盐具有相似特性的基本磁相互作用机制。