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Abstract The rapid development of computing applications demands novel low‐energy consumption devices for information processing. Among various candidates, magnetoelectric heterostructures hold promise for meeting the required voltage and power goals. Here, a route to low‐voltage control of magnetism in 30 nm Fe0.5Rh0.5/100 nm 0.68PbMg1/3Nb2/3O3‐0.32PbTiO3(PMN‐PT) heterostructures is demonstrated wherein the magnetoelectric coupling is achieved via strain‐induced changes in the Fe0.5Rh0.5mediated by voltages applied to the PMN‐PT. We describe approaches to achieve high‐quality, epitaxial growth of Fe0.5Rh0.5on the PMN‐PT films and, a methodology to probe and quantify magnetoelectric coupling in small thin‐film devices via studies of the anomalous Hall effect. By comparing the spin‐flop field change induced by temperature and external voltage, the magnetoelectric coupling coefficient is estimated to reach ≈7 × 10−8 s m−1at 325 K while applying a −0.75 V bias.
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Scalable Programming of LaAlO 3 /SrTiO 3 Interfaces via Ultra‐Low‐Voltage Electron‐Beam Lithography
Abstract Interface engineering at complex oxide heterostructures enables a wide range of electronic functionalities critical for next‐generation devices. Here it is demonstrated that ultra‐low‐voltage electron beam lithography (ULV‐EBL) creates high‐quality mesoscale structures at LaAlO3/SrTiO3(LAO/STO) interfaces with greater efficiency than conventional methods. Nanowires, tunnel barriers, and electron waveguides are successfully patterned that exhibit distinctive transport characteristics including 1D superconductivity, nonlinear current–voltage behavior, and ballistic electron flow. While conductive atomic force microscopy (c‐AFM) previously enabled similar interface modifications, ULV‐EBL provides significantly faster patterning speeds (10 mm s−1vs 1 µm s−1), wafer‐scale capability (>(10 cm)2vs <(90 µm)2), and maintenance of pattern quality under vacuum conditions. Additionally, an efficient oxygen plasma treatment method is developed for pattern erasure and surface cleaning, which reveals novel surface reaction dynamics at oxide interfaces. These capabilities establish ULV‐EBL as a versatile approach for scalable interface engineering in complex oxide heterostructures, with potential applications in reconfigurable electronics, sensors, and oxide‐based devices.
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- Award ID(s):
- 2225888
- PAR ID:
- 10640121
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 12
- Issue:
- 21
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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