3 research outputs found
Oxide Heteroepitaxy for Flexible Optoelectronics
The
emerging technological demands for flexible and transparent electronic
devices have compelled researchers to look beyond the current silicon-based
electronics. However, fabrication of devices on conventional flexible
substrates with superior performance are constrained by the trade-off
between processing temperature and device performance. Here, we propose
an alternative strategy to circumvent this issue via the heteroepitaxial
growth of transparent conducting oxides (TCO) on the flexible mica
substrate with performance comparable to that of their rigid counterparts.
With the examples of ITO and AZO as a case study, a strong emphasis
is laid upon the growth of flexible yet epitaxial TCO relying muscovite’s
superior properties compared to those of conventional flexible substrates
and its compatibility with the present fabrication methods. Besides
excellent optoelectro-mechanical properties, an additional functionality
of high-temperature stability, normally lacking in the current state-of-the-art
transparent flexitronics, is provided by these heterostructures. These
epitaxial TCO electrodes with good chemical and thermal stabilities
as well as mechanical durability can significantly contribute to the
field of flexible, light-weight, and portable smart electronics
Flexible Multiferroic Bulk Heterojunction with Giant Magnetoelectric Coupling <i>via</i> van der Waals Epitaxy
Magnetoelectric nanocomposites have
been a topic of intense research due to their profound potential in
the applications of electronic devices based on spintronic technology.
Nevertheless, in spite of significant progress made in the growth
of high-quality nanocomposite thin films, the substrate clamping effect
still remains a major hurdle in realizing the ultimate magnetoelectric
coupling. To overcome this obstacle, an alternative strategy of fabricating
a self-assembled ferroelectric–ferrimagnetic bulk heterojunction
on a flexible muscovite <i>via</i> van der Waals epitaxy is
adopted. In this study, we investigated the magnetoelectric coupling
in a self-assembled BiFeO<sub>3</sub> (BFO)–CoFe<sub>2</sub>O<sub>4</sub> (CFO) bulk heterojunction epitaxially grown on a flexible
muscovite substrate. The obtained heterojunction is composed of vertically
aligned multiferroic BFO nanopillars embedded in a ferrimagnetic CFO
matrix. Moreover, due to the weak interaction between the flexible
substrate and bulk heterojunction, the interface is incoherent and,
hence, the substrate clamping effect is greatly reduced. The phase-field
simulation model also complements our results. The magnetic and electrical
characterizations highlight the improvement in magnetoelectric coupling
of the BFO–CFO bulk heterojunction. A magnetoelectric coupling
coefficient of 74 mV/cm·Oe of this bulk heterojunction is larger
than the magnetoelectric coefficient reported earlier on flexible
substrates. Therefore, this study delivers a viable route of fabricating
a remarkable magnetoelectric heterojunction and yet flexible electronic devices
that are robust against extreme conditions with optimized performance
Heteroepitaxy of Fe<sub>3</sub>O<sub>4</sub>/Muscovite: A New Perspective for Flexible Spintronics
Spintronics
has captured a lot of attention since it was proposed. It has been
triggering numerous research groups to make their efforts on pursuing
spin-related electronic devices. Recently, flexible and wearable devices
are in a high demand due to their outstanding potential in practical
applications. In order to introduce spintronics into the realm of
flexible devices, we demonstrate that it is feasible to grow epitaxial
Fe<sub>3</sub>O<sub>4</sub> film, a promising candidate for realizing
spintronic devices based on tunneling magnetoresistance, on flexible
muscovite. In this study, the heteroepitaxy of Fe<sub>3</sub>O<sub>4</sub>/muscovite is characterized by X-ray diffraction, high-resolution
transmission electron microscopy, and Raman spectroscopy. The chemical
composition and magnetic feature are investigated by a combination
of X-ray photoelectron spectroscopy and X-ray magnetic circular dichroism.
The electrical and magnetic properties are examined to show the preservation
of the primitive properties of Fe<sub>3</sub>O<sub>4</sub>. Furthermore,
various bending tests are performed to show the tunability of functionalities
and to confirm that the heterostructures retain the physical properties
under repeated cycles. These results illustrate that the Fe<sub>3</sub>O<sub>4</sub>/muscovite heterostructure can be a potential candidate
for the applications in flexible spintronics