论文标题
Moiré超晶格的分数填充物的相关状态的激子和valleytronic签名
Excitonic and valleytronic signatures of correlated states at fractional fillings of a moiré superlattice
论文作者
论文摘要
Moiré超晶格是实现密切相关的量子现象的绝佳平台，例如Mott绝缘和超导性。特别是，最近的研究揭示了Moiré超晶格的分数填充物的条纹阶段和广义的Wigner晶体。但是，这些实验并未集中在电子结晶对超晶格的激子和valleytronic特性的影响上。在这里，我们报告了wse $ _2 $ _2 $/ws $ _2 $MoiréSuperlattice在分数填充物处的相关状态的激子和Valleytronic签名。我们观察到在填充因子$ν$ = 1/3和2/3处的三个内部Moiré激子的反射光谱调制。我们还观察到在大约十几个分数填充因子上的层间Trions的发光光谱调制，包括$ν$ = -3/2、1/4、1/3、2/3、2/5、2/3、6/7、5/3。另外，在某些部分填充物中，层间三层的山谷极化被明显抑制。这些结果表明了一种新的光 - 物质相互作用，其中电子结晶显着调节了Moiré超晶格中激子状态的吸收，发射和山谷动力学。
Moiré superlattices are excellent platforms to realize strongly correlated quantum phenomena, such as Mott insulation and superconductivity. In particular, recent research has revealed stripe phases and generalized Wigner crystals at fractional fillings of moiré superlattices. But these experiments have not focused on the influence of electronic crystallization on the excitonic and valleytronic properties of the superlattices. Here we report excitonic and valleytronic signatures of correlated states at fractional fillings in a WSe$_2$/WS$_2$ moiré superlattice. We observe reflection spectral modulation of three intralayer moiré excitons at filling factors $ν$ = 1/3 and 2/3. We also observe luminescence spectral modulation of interlayer trions at around a dozen fractional filling factors, including $ν$ = -3/2, 1/4, 1/3, 2/5, 2/3, 6/7, 5/3. In addition, the valley polarization of interlayer trions is noticeably suppressed at some fractional fillings. These results demonstrate a new regime of light-matter interactions, in which electron crystallization significantly modulates the absorption, emission, and valley dynamics of the excitonic states in a moiré superlattice.
