在费米-哈伯德模拟器中的挫折和兴奋剂诱导的磁性
Muqing Xu1, Lev Haldar Kendrick1, Anant Kale1
1Department of Physics, Harvard University, Cambridge, MA, USA.
Nature
|August 2, 2023
概括
强烈相关的系统中的几何挫折驱动磁相的转变. 可调节光学网中的超冷费米子揭示了挫折如何影响磁性相关性和兴奋剂效应.
科学领域:
- 凝聚物质物理学
- 量子磁力学
- 超冷的原子气体
背景情况:
- 强烈相关的系统中的几何挫折会导致新的量子自旋液体和磁相.
- 哈伯德对异型三角格子的模型是研究强相关性和磁的关键模型.
- 兴奋剂对挫败磁性的影响及其与方格哈巴德模型的关系尚不清楚.
研究的目的:
- 调查哈巴德模型的局部旋转顺序,
- 为了理解从尼尔反铁磁到120度螺旋阶段的过渡,由于丧.
- 在三角形和方形格子Hubbard模型中探索磁性相关性的兴奋剂效应.
主要方法:
- 在异型光学网格中利用超冷费米子.
- 连续调整格子的几何形状从正方形到三角形.
- 在强相互作用 (U/t ≈ 9) 和不同的兴奋剂水平下研究了哈巴德模型.
主要成果:
- 观察到的挫折减少了磁对应范围,并在半填充时从Néel转向120°螺旋阶段.
- 在三角边界的孔中发现了增强的反铁磁相关性.
- 观察到铁磁关联的反转在粒子注超过20%,表明动力磁性的作用.
结论:
- 在光学网格中可控制的丧和注提供了对复杂磁相的洞察力.
- 这项研究强调了几何丧,相关性和兴奋剂在确定磁性秩序之间的相互作用.
- 这项工作开辟了探索奇拉相,三角格子中的超导和酸超导模型的途径.
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