
**Ferroelectric switching of spin-to-charge conversion for ultralow power
spintronics**
Christian Rinaldi
[christian.rinaldi@polimi.it](mailto:christian.rinaldi@polimi.it)
Dipartimento di Fisica, Politecnico di Milano, Milan, Italy
Information and communication technology is going to use 20% of the global
electricity production by 2030. Architectures far beyond the well-established
CMOS platform are required for electronics to switch greener. A remarkable
pathway was indicated by Intel in the work titled “Beyond CMOS computing
with spin and polarization†[1, 2], where the combination of ferroics and
spin currents was shown to be a master choice for attojoule-class logic
devices.
Ferroelectric Rashba semiconductors (FERSC) [3] such as germanium telluride
(GeTe) [4] emerge in this scenario, thanks to their intrinsic combination of
ferroelectricity and electric controllability of spin currents in single
materials.
Here we demonstrate that the ferroelectric polarization of epitaxial thin
films of GeTe can be reliably switched back and forth by electrical gating and
used to effectively reverse a sizeable spin-to-charge conversion by spin Hall
effect [5]. Doping and alloying with indium and tin will be shown as
perspective to achieve control over conductivity and spin-to-charge
conversion. Based on these results, we will show the possibility to develop
scalable and energy-efficient non-volatile ferroelectric spin-orbit logic
devices, in which information is conveniently stored in the ferroelectric
state, while processing and read-out are enabled by polarization-dependent
spin-to-charge conversion.
Endowed of monolithic integrability with silicon, GeTe and its alloys may
represent a viable path towards spintronic-based transistors with ultralow
power consumption.
* **References**
* [1] S. Manipatruni, D. E. Nikonov and I. A. Young, “Beyond CMOS computing with spin and polarizationâ€, Nature Physics 14, 338 (2018).
* [2] Diogo C. Vaz et al., “Voltage-based magnetization switching and reading in magnetoelectric spin-orbit nanodevicesâ€, ArXiv pre-print arXiv:2302.12162.
* [3] S. Picozzi, “Ferroelectric Rashba semiconductors as a novel class of multifunctional materialsâ€, Frontiers in Physics 2, 1 (2014).
* [4] D. Di Sante, P. Barone, R. Bertacco and S. Picozzi, “Electric control of the giant Rashba effect in bulk GeTeâ€, Advanced Materials 25, 509 (2013).
* [5] S. Varotto, C. Rinaldi et al., “Room-temperature ferroelectric switching of spin-to-charge conversion in germanium tellurideâ€, Nature Electronics 4, 740 (2021).
**Host:** L. Hueso & F. Casanova