The valley Zeeman physics of excitons in monolayer transition metal dichalcogenides provides valuable insight into the spin and orbital degrees of freedom inherent to these materials. Being atomicallythin materials, these degrees of freedom can be influenced by the presence of adjacent layers, due to proximity interactions that arise from wave function overlap across the 2D interface. Here, we report 60 T magnetoreflection spectroscopy of the A and B excitons in monolayer WS_{2}, systematically encapsulated in monolayer graphene. While the observed variations of the valley Zeeman effect for the A exciton are qualitatively in accord with expectations from the bandgap reduction and modification of the exciton binding energy due to the grapheneinduced dielectric screening, the valley Zeeman effect for the B exciton behaves markedly different. We investigate prototypical WS_{2}/graphene stacks employing firstprinciples calculations and find that the lower conduction band of WS_{2}at the
Nearperfect light absorbers (NPLAs), with absorbance,
 NSFPAR ID:
 10427964
 Publisher / Repository:
 Nature Publishing Group
 Date Published:
 Journal Name:
 Nature Communications
 Volume:
 14
 Issue:
 1
 ISSN:
 20411723
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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