Superconductor/ferroic hybrids
DIPC Seminars
- Speaker
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Javier E. Villegas , Unité Mixte de Physique CNRS/Thales
- When
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2013/06/14
14:00 - Place
- Donostia International Physics Center (DIPC).Paseo Manuel de Lardizabal, 4 (nearby the Facultad de Quimica), Donostia
- Add to calendar
-
iCal
**Superconductor/ferroic hybrids**
Javier E. Villegas
Unité Mixte de Physique CNRS/Thales, Palaiseau, France
The physical properties of hybrid structures may radically differ from those
of the individual constituents’, as novel -sometimes unexpected- behaviors
arise due to competing interactions at the interfaces. Interestingly, external
stimuli that have moderate effects on each of the constituents separately may
induce dramatic effects on the hybrid structure, as they break the delicate
balance resulting from the interface interactions. This allows engineering
artificial materials with new functionalities [1]. Superconductor/ferroic
hybrids provide with many examples of this.
One interesting possibility is to couple one of the constituents’
sensitivity to external stimuli (e.g. electric or magnetic fields) to a
measurable, strongly varying physical property of the other constituent (e.g.
the electrical resistance in a superconductor). I will show that this is
possible via the effects on the superconductor of the (magnetic or electric)
stray fields from the ferromagnetic [2] or ferroelectric subsystem [3,4].
These effects yield a giant, hysteretic, remnant magneto (or electro)
resistance. Furthermore, through this mechanism and owing to the ability to
reversibly design the ferroic domain structure, it is possible to produce a
nanoscale modulation of the superconducting condensate [3]. This opens new
possibilities for superconducting nano-electronic devices, which may exploit
flux quantization [5,6] and Josephson coupling effects.
Another interesting possibility is to literally merge the most distinctive
property of each of the constituents in order to observe truly hybridized
behavior. In the second part of the talk, we will show an example on how to
unite the long-range phase-coherent charge transport characteristic of
superconductivity and the spin-polarized charge transport characteristic of
ferromagnetism [7], which may open the door to novel spintronic devices. This
is demonstrated in experiments with heterostructures that combine YBa2Cu3O7-x
and the half-metallic ferromagnet La0.7Ca0.3MnO3. [8]
**References**
[1] M. Bibes, J. E. Villegas and A. Barthélémy, Advances in Physics, **60**
(2011) 5.
[2] C. Visani, P. J. Metaxas, A. Collaudin, B. Calvet, R. Bernard, J.
Briatico, C. Deranlot, K. Bouzehouane, and J. E. Villegas, Phys. Rev. B **84**
, 054539 (2011).
[3] A. Crassous, R. Bernard, S. Fusil, K. Bouzehouane, D. Le Bourdais, S.
Enouz-Vedrenne, J. Briatico, M. Bibes, A. Barthélémy, and Javier E.
Villegas, Phys. Rev. Lett. **107** (2011) 247002\.
[4] A. Crassous, R. Bernard, S. Fusil, K. Bouzehouane, J. Briatico, M.
Bibes, A. Barthélémy, and Javier E. Villegas, Jour. Appl. Phys. **113**
(2013) 024910.
[5] _ _ I. Swiecicki, C. Ulysse, T. Wolf, R. Bernard, N. Bergeal, J.
Briatico, G. Faini, J. Lesueur and J. E. Villegas, __ Phys. Rev. B **85**
(2012) 224502.
[6] J. E. Villegas, _et al. _Nanotechnology 22 (2011) 075302.
[7] F. S. Bergeret, A. F. Volkov, and K. B. Efetov, Rev. Mod. Phys. 77, 1321
(2005).
[8] C. Visani, Z. Sefrioui, J. Tornos, C. León, J. Briatico, M. Bibes, A.
Barthélémy, J. Santamaría and Javier E. Villegas, Nature Physics **8**
(2012) 539.