论文标题
通过库仑相互作用破坏石墨烯量子点中无质量毛茸茸的费米的窃窃私语模式
Breaking whispering-gallery modes of massless Dirac fermions in graphene quantum dots by Coulomb interaction
论文作者
论文摘要
库仑相互作用在局部能级（结合状态）或电子平坦带中至关重要，并且可能导致许多异国情调的量子相，例如石墨烯系统中的磁性，超导和拓扑相1-14。在石墨烯单层中，电荷载体的相对论无质量的泥土式性质使我们能够实现前所未有的quasibound状态，这些状态被左撇子 - 寿命（捕获时间）暂时捕获，左右的石化量（GQD）（gqds）以〜10 fs为〜10 fs。在这里，我们表明库仑相互作用在确定暂时限制的准圆形状态的电子特性中仍然起着主导作用。我们的扫描隧道显微镜（STM）和光谱法（STS）测量表明，当部分填充时，GQD中的离散的quasibound态将分为两个峰。两个分裂峰的能量分离与GQD的反相反半径增加线性，表明分裂是由库仑相互作用引起的。此外，我们表明，这两个分裂状态的实际空间分布在GQD的不同区域分离以减少库仑相互作用，从而导致Quasibound状态的WGM破坏。
Coulomb interaction is of central importance in localized energy levels (bound states) or electronic flat bands and could result in many exotic quantum phases, such as magnetic, superconducting, and topological phases in graphene systems1-14. In graphene monolayer, the relativistic massless Dirac fermion nature of the charge carriers enables us to realize unprecedented quasibound states, which are trapped temporarily via whispering-gallery modes (WGMs) with the lifetime (trapping time) of ~ 10 fs, in circular graphene quantum dots (GQDs)15-20. Here we show that Coulomb interaction still plays a dominating role in determining the electronic properties of the temporarily-confined quasibound states. Our scanning tunneling microscopy (STM) and spectroscopy (STS) measurements demonstrate that the discrete quasibound state in a GQD will split into two peaks when it is partially filled. The energy separation of the two split peaks increases linear with inverse effective radius of the GQDs, indicating that the splitting arises from the Coulomb interaction. Moreover, we show that the real space distribution of the two split states separates in different regions of the GQD to reduce the Coulomb interaction, leading to the breaking of the WGM of the quasibound states.
