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Internship (and PhD) Offer
Study of a new memristive material
Memristors have been theoretically predicted by Leon Chua in 1971 [1] to be the fourth
electrical component, relating electric charge and magnetic flux. They have been claimed to be
experimentally realized by Strukov in 2008 [2]. They are particularly interesting for applications
and it has been recently realized that RRAM (resistive random access memories) are memristors[3].
We have synthetized and studied a new family of lamellar titanium oxides that exhibit
ferroelectric behaviour as well as memristives properties. The microscopic mechanism for the
ferroelectricity is unclear and most probably unconventional. It most certainly involves non-trivial
ionic motion inside the material.
The aim of the internship is to pursue this work in order to understand the microscopic
mechanism at play, by performing electrical measurements (electrical constant, I-V curves and
relaxation measurements), X-Ray diffraction, Raman spectroscopy, piezoresponse measurements
and magnetization measurements. The internship period will be mainly devoted to electrical
measurements. A substantial part of work will be devoted to modelling the observed effects.
The outcome of the project is twofold : elucidating the microscopic behaviour of the
samples, and evaluating the possibility of making practical devices out of this material.
The applicant should possess a solid background in material physics. He (She) will get the
possibility to learn a wide variety of techniques (including sample fabrication). He (she) should be
highly motivated by experimental work and modelization and should be very well adapted to
collaborations and interactions with other groups.
The experiments will be conducted mostly in the group of Dr. Leridon, ESPCI, Paris. Part of
the experiments will be conducted in other universities in Paris.
[1] Leon O Chua. Memristor - the missing circuit element. Circuit Theory, IEEE
Transactions on, 18(5) , 507 (1971).
[2] Dmitri B Strukov, Gregory S Snider, Duncan R Stewart, and R Stanley Williams.
The missing memristor found. Nature, 453(7191), 80 (2008)
[3] Leon Chua. Resistance switching memories are memristors. Applied Physics A,
102(4), 765, (2011)