论文标题
石墨烯中脱落式Landau水平的量子点辅助光谱
Quantum-Dot Assisted Spectroscopy of Degeneracy-Lifted Landau Levels in Graphene
论文作者
论文摘要
强相互作用阶段的能量光谱需要探针，以最大程度地减少筛选，同时保持光谱分辨率和局部灵敏度。在这里，我们证明可以使用与六角硼硝化隧道壁垒的缺陷结合的原子大小的量子点来实现此类探针，该探针位于距离石墨烯的纳米距离处。通过通过平面石墨电极调谐的点能量，点辅助的隧道对石墨烯激发光谱高度敏感。 The spectra track the onset of degeneracy lifting with magnetic field at the ground state, and at unoccupied exited states, revealing symmetry-broken gaps which develop steeply with magnetic field - corresponding to Landé $g$ factors as high as 160. Measured up to $B = 33$ T, spectra exhibit a primary energy split between spin-polarized excited states, and a secondary spin-dependent valley-split.我们的结果表明，缺陷点探测了光谱的同时最大程度地减少局部筛选，因此对相互作用状态非常敏感。
Energy spectroscopy of strongly interacting phases requires probes which minimize screening while retaining spectral resolution and local sensitivity. Here we demonstrate that such probes can be realized using atomic sized quantum dots bound to defects in hexagonal Boron Nitride tunnel barriers, placed at nanometric distance from graphene. With dot energies capacitively tuned by a planar graphite electrode, dot-assisted tunneling becomes highly sensitive to the graphene excitation spectrum. The spectra track the onset of degeneracy lifting with magnetic field at the ground state, and at unoccupied exited states, revealing symmetry-broken gaps which develop steeply with magnetic field - corresponding to Landé $g$ factors as high as 160. Measured up to $B = 33$ T, spectra exhibit a primary energy split between spin-polarized excited states, and a secondary spin-dependent valley-split. Our results show that defect dots probe the spectra while minimizing local screening, and are thus exceptionally sensitive to interacting states.
