Toward room temperature superconductivity
UPDATE: Prof. Kempa just (Aug 6) published the Article Strong enhancement of superconductivity via engineered dielectric environmenta on arxiv.
Join us at the first Colloquium@T2P on
Toward room temperature superconductivity via engineered dielectric response of the environment
Prof. Krzysztof Kempa
Boston College, United States // Email: kris.kempa@bc.edu
Abstract:
It has been known that superconductivity can be enhanced by engineering the dielectric environment of a superconductor. This enhancement is maximized due to the resonant anti-shielding effect (RAS) when the nonlocal dielectric function ε(ω,k) of the environment satisfies the following “epsilon near zero” (ENZ) condition |ε(ω,k)| → 0. This effect is universal, since it relies on the fact that Cooper pairs, regardless of the pairing mechanism are simply charges that can be affected by external charges induced in the engineered dielectric environment. Yet, not much progress has been achieved along this strategy. We identify the key reasons for this, and discuss two systems where the required stringent conditions can be satisfied. First system is the atomic scale superlattice structure consisting of alternating layers of topological crystal (Bi2Se3), and the MgB2 superconductor. We show, that the recently discovered plasmon-polaron collective excitation of the Dirac electrons in Bi2Se3 is capable, via RAS effect of boosting the corresponding Tc a factor of 4 in this system. The second system is similar, except in the atomic scale superlattice Bi2Se3 film is replaced with a Mo2(INA)4 metal-organic framework (MOF) 2D single crystal film. In this system the RAS effect is even stronger and more controllable, and our estimates show that a room temperature operation might be achievable. We have also considered a possibility of using cuprates as an alternative to MgB2.
The talk will also be broadcast via Zoom:
Zoom Link: https://hu-berlin.zoom-x.de/j/61309459269?pwd=WoEFadUNorOk8YwSEWH3ADZlRJQ1eh.1
Meeting ID: 613 0945 9269
Password: 899503