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Direct electrical modulation of second-order optical susceptibility via phase transitions


Electrical modulation of nonlinear optical signals is crucial for emerging applications in communications and photonic circuits. However, current methods of modulating the second-order optical susceptibility involve indirectly and inefficiently changing the third-order susceptibility. Here we show that electrical switching of the crystal structure of monolayer molybdenum ditelluride can be used to directly modulate the second-order susceptibility. This approach leads to modulation of the second-harmonic generation with an on/off ratio of 1,000 and modulation strength of 30,000% per volt, as well as broadband operation of 300 nm. We also show that molybdenum ditelluride bilayers exhibit opposite modulation trends due to electrically induced heterostructures.

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Fig. 1: Direct electrical modulation of second-order optical susceptibility χ(2) based on layered MoTe2.
Fig. 2: Broadband and giant SHG tunability in monolayer MoTe2 through electrically induced phase transition.
Fig. 3: Extremely high SHG modulation strength on a monolayer MoTe2 device.
Fig. 4: Layer-dependent SHG modulation and electrically induced 1T'/1H heterostructures.

Data availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.


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This work is supported by the Gordon and Betty Moore Foundation (award no. 5722) and the Ernest S. Kuh Endowed Chair Professorship.

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Authors and Affiliations



Y.W. and X.Z. initiated the research and designed the experiments. Y.W. and J.X. performed the SHG measurements. Y.W. and T.-F.C. fabricated the devices. Y.W. J.X., Z.N. and S.Y. analysed the data with X.Z. All the authors contributed to the writing of the manuscript.

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Correspondence to Xiang Zhang.

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The authors declare no competing interests.

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Peer review information Nature Electronics thanks Ueli Koch, Zheng Liu and Shuang Zhang for their contribution to the peer review of this work.

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Supplementary Information

Supplementary Discussion and Figs. 1–8.

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Wang, Y., Xiao, J., Chung, TF. et al. Direct electrical modulation of second-order optical susceptibility via phase transitions. Nat Electron 4, 725–730 (2021).

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