Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2010-09-26
Phys.Rev.B83:115438,2011
Physics
Condensed Matter
Strongly Correlated Electrons
12 pages, 1 figure
Scientific paper
10.1103/PhysRevB.83.115438
The Coulomb interaction between massless Dirac fermions may induce dynamical chiral symmetry breaking by forming excitonic pairs in clean graphene, leading to semimetal-insulator transition. If the Dirac fermions have zero bare mass, an exact continuous chiral symmetry is dynamically broken and thus there are massless Goldstone excitons. If the Dirac fermions have a small bare mass, an approximate continuous chiral symmetry is dynamically broken and the resultant Goldstone type excitons become massive, which is analogous to what happens in QCD. In this paper, after solving Dyson-Schwinger gap equation in the presence of a small bare fermion mass, we found a remarkable reduction of the critical Coulomb interaction strength for excitonic pair formation and a strong enhancement of dynamical fermion mass. We then calculate the masses of Goldstone type excitons using the SVZ sum rule method and operator product expansion technique developed in QCD and find that the exciton masses are much larger than bare fermion mass but smaller than dynamical fermion mass gap. We also study the spin susceptibilities and estimate the masses of non-Goldstone type excitons using the same tools.
Huang Ming-Qiu
Liu Guo-Zhu
Zhang Chun-Xu
No associations
LandOfFree
Dynamical fermion mass generation and exciton spectra in graphene does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Dynamical fermion mass generation and exciton spectra in graphene, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dynamical fermion mass generation and exciton spectra in graphene will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-561816