We are excited to share that Jing Song's new paper has been published in Phys. Rev. X.

Paper title: Observation of Wannier-Rydberg and charge-transfer hybrid moiré excitons under pressure

Citation: Phys. Rev. X 16, 041007 (2026)

In this work, we demonstrate that hydrostatic pressure provides an effective way to engineer moiré excitons in WSe₂/WS₂ heterobilayers. By combining a diamond anvil cell with dual-gate optical spectroscopy at low temperatures, we find that increasing pressure significantly enhances the moiré potential. Remarkably, above approximately 3 GPa, a new exciton state emerges. Our theoretical calculations reveal that this state originates from strong hybridization between Wannier-Rydberg 3d excitons and charge-transfer excitons, exhibiting unique orbital and spatial characteristics. We also observe substantially enhanced exciton-electron and exciton-exciton interactions under pressure. These findings establish hydrostatic pressure as a powerful tool for engineering exciton wavefunctions and interactions, opening new possibilities for exploring strongly correlated excitonic phenomena in moiré superlattices.

We are excited to share that Xuan Zhao's new paper has been published in Nano Letters.

Paper title: Pressure Tuning of Layer-hybridized Excitons in Trilayer WSe2.

Citation: Nano Letters 26, 1035-1042 (2026)

van der Waals (vdW) forces in two-dimensional materials allow for versatile control over interlayer coupling, enabling the exploration of novel emergent quantum states and device functionalities. Here, using microreflectance spectroscopy in a diamond anvil cell, we demonstrate dynamic pressure tuning of layer-hybridized excitons in dual-gated trilayer WSe₂ devices up to 6.6 GPa. Pressure-controlled interlayer coupling manifests as enhanced energy-level anticrossings and oscillator strength redistribution between the intralayer and interlayer excitons. We observe an 11% reduction in the interlayer exciton dipole moment, while the coupling strength triples (from ∼10 to >30 meV), following a near-linear scaling of 3.5 ± 0.2 meV/GPa. Spectral density simulations resolve four distinct components of hybridized excitons, i.e., intralayer ground/excited and interlayer ground/excited states, with their relative weights transitioning from one component dominant to strongly mixed at higher pressures. Our findings highlight the potential for controlling excitonic properties and engineering optoelectronic devices through interlayer compression.