Topological classification and stability of Fermi surfaces.

Title Topological Classification and Stability of Fermi Surfaces

Stability of Fermi surfaces and K theory.

Nonrelativistic Fermi liquids in d+1 dimensions exhibit generalized Fermi surfaces: (d-p)-dimensional submanifolds in the (k,omega)-space supporting gapless excitations. We show that the universality classes of stable Fermi surfaces are classified by K theory, with the pattern of stability determined by Bott periodicity. The Atiyah-Bott-Shapiro construction implies that the low-energy modes nea...

Majorana Fermions and Topology in Superconductors

Topological superconductors are novel classes of quantum condensed phases, characterized by topologically nontrivial structures of Cooper pairing states. On the surfaces of samples and in vortex cores of topological superconductors, Majorana fermions, which are particles identified with their own anti-particles, appear as Bogoliubov quasiparticles. The existence and stability of Majorana fermio...

Doping-dependent electronic structure of cuprates studied using angle-scanned photoemission

Full k‖-maps of the electronic structure near the Fermi level of differently doped cuprates measured with angle-scanned photoelectron spectroscopy are presented. The valence band maximum of the antiferromagnetic insulator Sr2CuO2Cl2, which is taken as a representative of an undoped cuprate, and the Fermi surfaces of overdoped, optimally doped and underdoped Bi2Sr2CaCu2O8+δ high-temperature supe...

A pr 2 00 3 Dynamical Systems , Topology and Conductivity in Normal Metals

New observable integer-valued numbers of the topological origin were revealed by the present authors studying the conductivity theory of single crystal 3D normal metals in the reasonably strong magnetic field (B ≤ 10 3 T l). Our investigation is based on the study of dynami-cal systems on Fermi surfaces for the motion of semi-classical electron in magnetic field. All possible asymptotic regimes...