Ferroelectric (FE) devices are conventionally switched by an application of an electric field. However, the recent discoveries of light–matter interactions in heterostructures based on 2D semiconductors and FE materials open new opportunities for using light as an additional tool for device programming. Recently, a purely optical switching of FE polarization in heterostructures comprising 2D MoS2and FE oxide perovskites, such as BaTiO3and Pb(Zr,Ti)O3(PZT), was demonstrated. In this work, it is investigated whether this optical switching has a practical value and can be used to improve functional characteristics of MoS2‐PZT FE field‐effect transistors for nonvolatile memory applications. It is demonstrated that the combined use of an electrical field and visible light improves the nonvolatile ON/OFF ratios in MoS2‐PZT memories by several orders of magnitude compared to their purely electrical operation. The memories are read at zero gate voltage (
In the ferroelectric devices, polarization control is usually accomplished by application of an electric field. In this paper, we demonstrate optically induced polarization switching in BaTiO3-based ferroelectric heterostructures utilizing a two-dimensional narrow-gap semiconductor MoS2as a top electrode. This effect is attributed to the redistribution of the photo-generated carriers and screening charges at the MoS2/BaTiO3interface. Specifically, a two-step process, which involves formation of intra-layer excitons during light absorption followed by their decay into inter-layer excitons, results in the positive charge accumulation at the interface forcing the polarization reversal from the upward to the downward direction. Theoretical modeling of the MoS2optical absorption spectra with and without the applied electric field provides quantitative support for the proposed mechanism. It is suggested that the discovered effect is of general nature and should be observable in any heterostructure comprising a ferroelectric and a narrow gap semiconductor.
more » « less- NSF-PAR ID:
- 10153579
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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