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Strain engineering is a natural route to control the electronic and optical properties of two-dimensional (2D) materials. Recently, 2D semiconductors have also been demonstrated as an intriguing host of strain-induced quantum-confined emitters with unique valley properties inherited from the host semiconductor. Here, we study the continuous and reversible tuning of the light emitted by such localized emitters in a monolayer tungsten diselenide embedded in a van der Waals heterostructure. Biaxial strain is applied on the emitters via strain transfer from a lead magnesium niobate–lead titanate (PMN-PT) piezoelectric substrate. Efficient modulation of the emission energy of several localized emitters up to 10 meV has been demonstrated on application of a voltage on the piezoelectric substrate. Further, we also find that the emission axis rotates by as the magnitude of the biaxial strain is varied on these emitters. These results elevate the prospect of using all electrically controlled devices where the property of the localized emitters in a 2D host can be engineered with elastic fields for an integrated opto-electronics and nano-photonics platform.
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This content will become publicly available on November 21, 2026
Enhanced polarizability and tunable diamagnetic shift from monolayer WSe2 on relaxor ferroelectric
Abstract Strain modulation is a crucial way in engineering nanoscale materials. It is even more important for single photon emitters in layered materials, where strain can trap a delocalized exciton, leading to quantum emission. Herein, we apply strain by using the piezoelectric relaxor ferroelectric substrate. In addition to the strain-tuning of energy and polarization, we report on new observations, including the enhanced polarizability and tunable diamagnetic shift, from the charged localized excitons. As indicated from the polarization-resolved measurements, we attribute the formation of charged localized excitons to selenium vacancy defects. The shallow defect trap, supported by the value of g-factor, further allows for strain-modulation of the electron-hole overlap, hence resulting in the tunable diamagnetic shift. Our results provide a new perspective in integrating layered materials with functional substrates. The contrasting features observed from the charged localized excitons also signify the prospect of charged localized emitters for quantum science and technology.
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- Award ID(s):
- 1752997
- PAR ID:
- 10652104
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- npj 2D Materials and Applications
- ISSN:
- 2397-7132
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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