Qantum Well Resonant Tunneling Diode Probe of Correlated States in Twisted Bilayer MoS${}_2$

Moiré superlattices formed in transition metal dichalcogenides (TMDs) offer a versatile platform for exploring emergent quantum phases arising from strong electronic correlations. In this work, we develop a new experimental platform, the quantum well resonant tunneling diode (QWRTD), to probe the electronic landscape of $\approx {57}^{\circ }$ twisted bilayer MoS${}_2$ (tMoS${}_2$). By measuring the differential conductance ($dI\mathrm{/}d{V}_{\text{Probe}}$) as a function of filling factor $\nu$ and displacement field $D$, we observe a robust integer correlated insulating state at $\nu =1$ that persists across the measured displacement field range. Furthermore, we identify a displacement-field-induced fractional insulating state at $\nu =3\mathrm{/}4$ for $D<-75$~mV/nm. Temperature- and magnetic-field-dependent measurements characterize this $\nu =3\mathrm{/}4$ state as a potential generalized Wigner crystal. These correlated states are also observed in another device with a similar twist angle ($\approx {56.5}^{\circ }$). Our results provide direct evidence of correlated states in near-AB-stacked tMoS${}_2$ and establish QWRTD as a powerful experimental tool for investigating strong correlations and topology in van der Waals heterostructures.