Topology of the Fermi surface wave functions and magnetic oscillations in metals

Topology of the Fermi surface wave functions and magnetic oscillations in metals
Leonid Glazman, Physics Department, Yale University
Leonid Glazman
Date and time: Wed, Oct 28, 2020 - 4:00pm
Refreshments at 3:45pm
Location: Remote by ZOOM
Category: Departmental Colloquium
Special notes:

Zoom connection details are sent out via email to the departmental mailing lists.  If you wish to have the Zoom link and/or be added to the mailing list please contact the colloquium organizers:  Nikolay (prokofev@umass.edu) and Carlo (carlod@umass.edu).

Abstract:

In the traditional Fermiology, the size and shape of the Fermi surface in a metal is often deduced from the period of magnetic oscillations of transport or thermodynamic characteristics, e.g., from the de Haas – van Alphen effect. We find that the Onsager phase -- the intercept g of the infinite-field asymptote of the oscillations -- yields information about the topology of the Fermi surface wave functions. The topological invariance of g originates from the symmetry of extremal orbits, which depends not only on the space group but also on the field orientation with respect to the crystal axes. The wavefunctions fall into 10 distinct classes stemming from the crystalline symmetry; transitions between the classes occur via magnetic breakdown.