We are the Theory group of LPS!

If you are interested in doing an internship with us, or want to visit and discuss, please contact any of our members.

We are a very collaborative group which covers a wide range of topics from material sciences (functional materials, topological and relativistic matter, magnetism and superconductivity...) and quantum systems (in low dimensions, under magnetic fields, in and out-of equilibrium...) to soft and bio- matter (colloids, liquid crystals...).

Explore and enjoy our site!

  • Most recent peer-reviewed publications are below.

Recent Publications

G. Abramovici, “Incompatible Coulomb hamiltonian extensions”, vol. 10, no. 1, p. 7280, 2020. WebsiteAbstract
We revisit the resolution of the one-dimensional Schrödinger hamiltonian with a Coulomb λ/|x| potential. We examine among its self-adjoint extensions those which are compatible with physical conservation laws. In the one-dimensional semi-infinite case, we show that they are classified on a U(1) circle in the attractive case and on $${\boldsymbol{(}}{\mathbb{R}},{\boldsymbol{+}}{\boldsymbol{\infty }}{\boldsymbol{)}}$$(R,+∞) in the repulsive one. In the one-dimensional infinite case, we find a specific and original classification by studying the continuity of eigenfunctions. In all cases, different extensions are incompatible one with the other. For an actual experiment with an attractive potential, the bound spectrum can be used to discriminate which extension is the correct one.
Y. Kalcheim, Camjayi, A., del Valle, J., Salev, P., Rozenberg, M., and Schuller, I. K., “Non-thermal resistive switching in Mott insulator nanowires”, vol. 11, no. 1, p. 2985, 2020. WebsiteAbstract
Resistive switching can be achieved in a Mott insulator by applying current/voltage, which triggers an insulator-metal transition (IMT). This phenomenon is key for understanding IMT physics and developing novel memory elements and brain-inspired technology. Despite this, the roles of electric field and Joule heating in the switching process remain controversial. Using nanowires of two archetypal Mott insulators—VO2 and V2O3 we unequivocally show that a purely non-thermal electrical IMT can occur in both materials. The mechanism behind this effect is identified as field-assisted carrier generation leading to a doping driven IMT. This effect can be controlled by similar means in both VO2 and V2O3, suggesting that the proposed mechanism is generally applicable to Mott insulators. The energy consumption associated with the non-thermal IMT is extremely low, rivaling that of state-of-the-art electronics and biological neurons. These findings pave the way towards highly energy-efficient applications of Mott insulators.