Influence of the moiré potential on the intrinsic properties of TMD heterobilayers a) False color map of the σ-PL emission from IX of S2 measured with a resolution of 10 mT in the vicinity of the two identified resonant magnetic fields. The magnetic field for every sharp peak is different and the resonance has a diagonal profile. The white line indicates the energy dependence of the excitonic g factor, whose slope is ∂g/∂E ≈ 7.5 eV −1 (at B ≈ 24.2 T) and 8.5 eV −1 (at B ≈ 24.9 T) for the two resonant magnetic fields. b) PL Emission spectrum (left axis) of the IX at B= 0 T of S2 with energy dependent g-factor value (right axis) extracted from the data of panel a.

Influence of the moiré potential on the intrinsic properties of TMD heterobilayers a) False color map of the σ-PL emission from IX of S2 measured with a resolution of 10 mT in the vicinity of the two identified resonant magnetic fields. The magnetic field for every sharp peak is different and the resonance has a diagonal profile. The white line indicates the energy dependence of the excitonic g factor, whose slope is ∂g/∂E ≈ 7.5 eV −1 (at B ≈ 24.2 T) and 8.5 eV −1 (at B ≈ 24.9 T) for the two resonant magnetic fields. b) PL Emission spectrum (left axis) of the IX at B= 0 T of S2 with energy dependent g-factor value (right axis) extracted from the data of panel a.

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Optical selection rules in monolayers of transition metal dichalcogenides and of their heterostructures are determined by the conservation of the z-component of the total angular momentum - J Z = L Z +S Z - associated with the C3 rotational lattice symmetry which assumes half integer values corresponding, modulo 3, to distinct states. Here we show,...

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... high magnetic fields required to reach this resonance prevent any direct application of this effect but this very efficient scattering mechanism can play a crucial role enabling energy level lifetime engineering in optical devices. The same phenomenon is observed in sample S2 as shown in Figure 4a. Due to the slightly smaller g factor for S2, the resonant magnetic fields for this sample are B = 24.25 T and B = 24.9 ...
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... to the slightly smaller g factor for S2, the resonant magnetic fields for this sample are B = 24.25 T and B = 24.9 T (see Figure 4a). In contrast to S1, the resonance occurs over a broader range of magnetic fields due to different emission components composing the IX emission feature [14,49], but appears in the form of the specific diagonal feature seen in Fig- ure 4a. ...
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... (see Figure 4a). In contrast to S1, the resonance occurs over a broader range of magnetic fields due to different emission components composing the IX emission feature [14,49], but appears in the form of the specific diagonal feature seen in Fig- ure 4a. The exciton-phonon resonance remains nevertheless extremely sharp for each emission peak composing the broad IX emission, still occurring over a variation of magnetic field as small as 100 mT. ...
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... for S2 the same phonon energies as in sample S1, the finesse of this exciton-phonon coupling enables to resolve the energy dependence of the excitonic g-factor, whose slope is ∂g/∂E ≈ 7.5 and 8.5 eV −1 for the two resonant magnetic fields, respectively. We also present in Figure 4b the values of g-factor extracted close to B ∼ 24.2 T together with the zero field IX spectrum (an alternative analysis can be found in the Supplementary Information Section S9-10). The magnitude of the slope as well as the fact that the exciton g-factor is determined by the excitation energy are consistent with the standard band theory expression for the orbital contribution g orb i to the g-factor of a single-electron band i due to virtual transitions to other bands j [50]: ...
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... ||i|ˆp||i|ˆp ± |j| 2 /m 0 is several eV, a few times larger than nearest band energy differences. If different components of the luminescence spectrum are due to random band energy variations across the sample, Eq. (1) gives ∂g/∂E of the order of a few eV −1 , in agreement with the experimental observation in Figure 4a. ...

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