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 excited 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.

相互作用强的相的能谱要求使用探针，以尽量减少筛选，同时保留光谱分辨率和局部灵敏度。在这里，我们证明了可以使用原子尺寸的量子点来实现这种探针，该量子点结合到六方氮化硼隧道势垒中的缺陷，并且距离石墨烯纳米距离。通过平面石墨电极电容性调整点能量，点辅助隧穿对石墨烯激发光谱变得高度敏感。该光谱在接地状态跟踪简并提升与磁场的发生，并且在未占用的激发态，揭示对称破碎间隙，其与磁场急剧发展-对应于朗德克因素高达160测量到乙 = 33 T，光谱显示出自旋极化激发态之间的一次能量分裂，以及次生自旋相关的谷值分裂。我们的结果表明，缺陷点在探测光谱的同时最小化了局部筛选，因此对相互作用状态异常敏感。