论文标题
Van der waals Heterostack中光生的层间激子的缩合特征
Condensation signatures of photogenerated interlayer excitons in a van der Waals heterostack
论文作者
论文摘要
由于具有较大的激子结合能和较长的寿命，原子范德华异源杂质是高温激子凝结的理想系统。电荷运输和电子损失光谱法显示了这种二维材料中激子多体状态的第一个证据。纯粹的光学研究，是访问光生激子相图的最明显方法是难以捉摸的。我们观察到在Mose2-WE2异质链接中托管的光增生激素集合的几个关键性相对于光致发光强度，线宽和时间相干性，指向过渡到相干量子状态。对于这种状态，职业为100％，激子扩散长度增加。该现象在10开Kelvin以上存活，与预测的临界冷凝温度一致。我们的研究提供了包括Bose Einstein凝结在内的多体层间激子状态的第一相三联。
Atomistic van der Waals heterostacks are ideal systems for high-temperature exciton condensation because of large exciton binding energies and long lifetimes. Charge transport and electron energy-loss spectroscopy showed first evidence of excitonic many-body states in such two-dimensional materials. Pure optical studies, the most obvious way to access the phase diagram of photogenerated excitons have been elusive. We observe several criticalities in photogenerated exciton ensembles hosted in MoSe2-WSe2 heterostacks with respect to photoluminescence intensity, linewidth, and temporal coherence pointing towards the transition to a coherent quantum state. For this state, the occupation is 100 percent and the exciton diffusion length is increased. The phenomena survive above 10 kelvin, consistent with the predicted critical condensation temperature. Our study provides a first phase-diagram of many-body interlayer exciton states including Bose Einstein condensation.
