Dynamic Quantum Matter

  • Dynamical multiferroicity: A static spin-spiral in space can, via the Dzyaloshiksii-Moriya interaction lead to an effective polarisation; by exploiting the duality between electricity and magnetism in Maxwell’s equations, a complementary effect – Dynamical Multiferroicity – is possible.
  • Pumped Dirac materials: Recent pump-probe experiments demonstrate the possibility that Dirac materials may be driven into transient excited states describable by two chemical potentials, one for the electrons and one for the holes. Given the Dirac nature of the spectrum, such an inverted population allows the optical tunability of the density of states of the electrons and holes, effectively offering control of the strength of the Coulomb interaction.
  • Odd frequency superconductivity: Due to the fermionic nature of electrons, the spatial symmetry (s-wave, p-wave, d-wave, etc.) of a superconducting gap is intimately related to the spin state (singlet or triplet) of the Cooper pairs making up the condensate. In the limit of equal-time pairing this relationship is quite simple, even-parity gaps (like s-wave, or d-wave) correspond to spin singlet states while odd-parity gaps (like p-wave or f -wave) correspond to spin triplet states. However, if the electrons are paired at unequal times the superconducting gap could be odd in time or, equivalently, odd in frequency, in which case the condensate could be even in spatial parity and spin triplet or odd in spatial parity and spin singlet.