| March 19, 16:00
Perturbative and large N computations for critical behaviour of Gross-Neveu models of graphene
Certain phase transitions in a graphene sheet are known to be described at criticality by an underlying continuum quantum field theory which is the Gross-Neveu model. While the Ising Gross-Neveu model has been widely studied for many years, perturbative and large N computations in the related chiral Heisenberg Gross-Neveu model have not been carried out to the same level of precision. In the talk we will review recent four loop renormalization of the Ising Gross-Neveu model before developing the large N expansion for the chiral Heisenberg Gross-Neveu case. In the latter case the first three terms of various critical exponents are determined including eta at O(1/N^3). To achieve this accuracy the large N conformal bootstrap method is used. Finally estimates of exponents are given for the values of N relevant to the graphene transitions and compared to Monte Carlo and functional renormalization group results as well as the epsilon expansion of four dimensional perturbation theory.
University of Liverpool
Seminar room 0.03, ETP
Contact: Michael Scherer