Informal seminar featuring Professor Anthony Leggett, University of Illinois
Professor Anthony Leggett - University of Illinois
One of the historically earliest proposals for implementing the idea of (partially) protected topological quantum computing involves the physical braiding of the Majorana fermions believed to exist in two-dimensional Fermi superfluids in which the order parameter has the so-called chiral ("p+ip") symmetry. (For many years a plausible candidate system was single-plane strontium ruthenate, but recent experiments have somewhat muddied the waters). The original theoretical paper on this topic (Ivanov 2001), and most of the subsequent literature on it, uses the Bogoliubov-de Gennes equations, thereby violating the principle of conservation of total particle number. In this informal talk I will report on some work with Yiruo Lin* which inter alia attempts to examine how far the standard conclusions continue to hold when we insist on conserving particle number.