Speaker
Description
Quantum geometry is a prominent concept in modern physics. In particular, the Riemannian metric in Hilbert space, called the quantum metric, is an essential ingredient to realize superconductivity in flat-band systems where conventional kinetic dynamics are quenched, making quantum-geometric phenomena one of the most exciting fields in the recent condensed matter community. In this talk, we show that such intriguing physics induced by the quantum metric also plays a crucial role in dense QCD matter under external magnetic fields. We analytically reveal that in the two-flavor color-superconducting state, the Meissner mass transverse to the magnetic field is dominated by the quantum metric of Landau levels. Remarkably, in the strong field limit, the scaling of such a transverse Meissner mass is topologically bounded at the pairing gap squared, which is a sharp contrast to the scaling by chemical potential in the color-flavor locking state. This characteristic scaling in the transverse responce leads to a potential microscopic basis for surviving low-frequency quasi-periodic oscillations in magnetar asteroseismology, providing a novel connection from condensed matter physics and QCD to astrophysics and cosmology.