论文标题
Hubbard模型基态的某些确切的多体结果可在小量子点阵列中测试
Certain exact many-body results for Hubbard model ground states testable in small quantum dot arrays
论文作者
论文摘要
我们介绍了与Hubbard模型中平坦带铁磁性有关的几种有趣的现象。第一个是数学定理，该定理表明某些条件在某些条件下必须以非铁磁性状态进行堕落。该定理通常适用且与几何学无关，但仅适用于原本填充的频段中的少量孔。第二个现象是一个特殊的例子，即直觉失败，颗粒在填充高能状态之前偏爱占据低能状态。最后，我们展示了一种铁磁性的模式，该模式出现在五角形和六角形的斑块中，大约为3/10和1/4。这些示例仅需要少量的晶格位点，并且可以在当前作为实验室自旋量子阵列的量子点阵列中观察到。
We present several interesting phenomena related to flatband ferromagnetism in the Hubbard model. The first is a mathematical theorem stating certain conditions under which a flatband ferromagnetic must necessarily be degenerate with a nonferromagnetic state. This theorem is generally applicable and geometry-independent, but holds only for a small number of holes in an otherwise filled band. The second phenomenon is a peculiar example where the intuition fails that particles prefer to doubly occupy low-energy states before filling higher-energy states. Lastly, we show a pattern of ferromagnetism which appears in small pentagonal and hexagonal plaquettes at filling factors of roughly 3/10 and 1/4. These examples require only a small number of lattice sites, and may be observable in quantum dot arrays currently available as laboratory spin qubit arrays.
