Math Phys/Phys seminar

Fyrirlesari: Jens H. Bárðarson, KTH Stockholm

Titill: On the chiral anomaly in Weyl semimetals

Staðsetning: VR-II 158
Tími:þriðjudagur 4. desember, kl. 13.30

Ágrip:

I will give an introduction to the physics of Weyl semimetals focussing on Fermi arcs and chiral anomaly. I will then discuss some transport properties of Weyl semimetals including strongly angular-dependent magnetotransport in the presence of long range disorder, and the difference between the longitudinal conductance in the presence of magnetic field and chiral pseudo-magnetic field. The latter points in opposite direction for opposite chiralities and can be induced, for example, by strain. This leads to a discussion of pseudo-landau levels and their connection with Fermi arcs and covariant and consistent chiral anomaly. I will also mention a new axial torsional contribution to the axial anomaly.

Math Phys seminar

Fyrirlesari: Aruna Rajagopal, University of Iceland

Titill: Shock and Rarefaction Waves in Out of Equilibrium Lifshitz Fluids

Staðsetning: VR-II 155
Tími: Fimmtudaginn 22. nóvember 22 kl. 13.30

Ágrip:

Motivated by the recent developments and interest in the emergence of a non equilibrium steady state or NESS, for a relativistic fluid, and its possible holographic dual, we follow a similar framework to study the properties of such a state for a non-relativistic Lifshitz fluid with a general scaling exponent. This is carried out by solving the Riemann problem for the NESS which develops between two semi-infinite heat reservoirs that are brought into contact, and studying the shock and rarefaction waves which emerge as solutions to this problem.

Math Phys seminar

Fyrirlesari: Daniel Areán, IFT Madrid

Titill: Breaking translations in AdS/CMT: Holographic Bad Metals

Staðsetning: Naustið (Endurmenntun)
Tími: Wednesday October 24, 13.30 – 14.30

Ágrip:

Math Phys seminar

Fyrirlesari: Tobias Zingg, Nordita

Titill: plasmons and physical density-density response from holography

Staðsetning: Aðalbygging A-069

Tími: Thursday October 4, at 1.20 -2.20 pm

Ágrip:

The holographic correspondence can be extended to identify plasmonic excitations in strongly correlated systems. These modes have relevance in the growing field of plasmonics, and play also a crucial role in relating properties of holographic ‘screened’ density-density response response functions to ‘physical’ density-density response functions, with the latter being the quantity actually related to experimental observation.

Math Phys seminar

Fyrirlesari: Kevin John Torres Grosvenor, Niels Bohr Institute

Titill: Nonrelativistic Naturalness and the quest for Emergent Lorentz Symmetry

Staðsetning: V-147 (VR-II)
Tími: Þriðjudagur 22. maí kl. 10:30

Ágrip:

I will discuss our proposal for a nonrelativistic solution to the Higgs mass hierarchy problem, its dependence on the emergence of various shift symmetries, and the role it might play in the search for a nonrelativistic theory of particle physics in which Lorentz symmetry emerges at „low“ energies.

Math Phys seminar

Fyrirlesari: Matteo Baggioli, Autonomous University of Barcelona

Titill: Holographic quantum phase transitions: time to get dirty!

Staðsetning: HB-5 (Háskólabíó)
Tími: Mánudagur 9. apríl kl. 10:50

Ágrip:

We study the effects of quenched one-dimensional disorder on the holographic Weyl semimetal quantum phase transition (QPT). We observe the smearing of the sharp QPT linked to the appearance of rare regions at the horizon where the local order parameter is non-zero. We discuss the role of the disorder correlation and we compare our results to the weakly coupled expectations from condensed matter theory and simulations. We analyze also the interplay of finite temperature and disorder and we find preliminary indications for the presence of log-oscillatory structures in the order parameter.