Staff directory David Pesquera Herrero

David Pesquera Herrero

Postdoctoral Researcher
MSCA-IF_USA
david.pesquera(ELIMINAR)@icn2.cat
Oxide Nanophysics

Publications

2021

  • Pyroelectric thin films - Past, present, and future

    Velarde G., Pandya S., Karthik J., Pesquera D., Martin L.W. APL Materials; 9 (1, 010702) 2021. 10.1063/5.0035735. IF: 3.819

    Pyroelectrics are a material class that undergoes a change in polarization as the temperature of the system is varied. This effect can be utilized for applications ranging from thermal imaging and sensing to waste-heat energy conversion to thermally driven electron emission. Here, we review recent advances in the study and utilization of thin-film pyroelectrics. Leveraging advances in modeling, synthesis, and characterization has provided a pathway forward in one of the more poorly developed subfields of ferroelectricity. We introduce the complex physical phenomena of pyroelectricity, briefly explore the history of work in this space, and highlight not only new advances in the direct measurement of such effects but also how our ability to control thin-film materials is changing our understanding of this response. Finally, we discuss recent advances in thin-film pyroelectric devices and introduce a number of potentially new directions the field may follow in the coming years. © 2021 Author(s).


2020

  • Beyond Expectation: Advanced Materials Design, Synthesis, and Processing to Enable Novel Ferroelectric Properties and Applications

    Kim J., Lupi E., Pesquera D., Acharya M., Zhao W., Velarde G.A.P., Griffin S., Martin L.W. MRS Advances; 2020. 10.1557/adv.2020.344. IF: 0.000

    Ferroelectrics and related materials (e.g., non-traditional ferroelectrics such as relaxors) have long been used in a range of applications, but with the advent of new ways of modeling, synthesizing, and characterizing these materials, continued access to astonishing breakthroughs in our fundamental understanding come each year. While we still rely on these materials in a range of applications, we continue to re-write what is possible to be done with them. In turn, assumptions that have underpinned the use and design of certain materials are progressively being revisited. This perspective aims to provide an overview of the field of ferroelectric/relaxor/polar-oxide thin films in recent years, with an emphasis on emergent structure and function enabled by advanced synthesis, processing, and computational modeling. Copyright © The Author(s), 2020, published on behalf of Materials Research Society by Cambridge University Press.


  • Beyond Substrates: Strain Engineering of Ferroelectric Membranes

    Pesquera D., Parsonnet E., Qualls A., Xu R., Gubser A.J., Kim J., Jiang Y., Velarde G., Huang Y.-L., Hwang H.Y., Ramesh R., Martin L.W. Advanced Materials; 32 (43, 2003780) 2020. 10.1002/adma.202003780. IF: 27.398

    Strain engineering in perovskite oxides provides for dramatic control over material structure, phase, and properties, but is restricted by the discrete strain states produced by available high-quality substrates. Here, using the ferroelectric BaTiO3, production of precisely strain-engineered, substrate-released nanoscale membranes is demonstrated via an epitaxial lift-off process that allows the high crystalline quality of films grown on substrates to be replicated. In turn, fine structural tuning is achieved using interlayer stress in symmetric trilayer oxide-metal/ferroelectric/oxide-metal structures fabricated from the released membranes. In devices integrated on silicon, the interlayer stress provides deterministic control of ordering temperature (from 75 to 425 °C) and releasing the substrate clamping is shown to dramatically impact ferroelectric switching and domain dynamics (including reducing coercive fields to <10 kV cm−1 and improving switching times to <5 ns for a 20 µm diameter capacitor in a 100-nm-thick film). In devices integrated on flexible polymers, enhanced room-temperature dielectric permittivity with large mechanical tunability (a 90% change upon ±0.1% strain application) is demonstrated. This approach paves the way toward the fabrication of ultrafast CMOS-compatible ferroelectric memories and ultrasensitive flexible nanosensor devices, and it may also be leveraged for the stabilization of novel phases and functionalities not achievable via direct epitaxial growth. © 2020 Wiley-VCH GmbH