Based on three-dimensional quantum electrodynamics theory,a set of truncated Dyson-Schwinger（D-S） equations are solved to study photon and fermion propagators with the effect of vacuum polarization.Numerical studies...Based on three-dimensional quantum electrodynamics theory,a set of truncated Dyson-Schwinger（D-S） equations are solved to study photon and fermion propagators with the effect of vacuum polarization.Numerical studies show that condensation and the value of fermion mass depends heavily on how the D-S equations are truncated.By solving a set of coupled D-S equations,it is also found that the fermion propagator shows a clear dependence on the order parameter.The truncated D-S equations under unquenched approximation are used to study the mass-function and chiral condensation of the fermions.The results under the unquenched approximation are clearly different from the ones under quenched approximation.With the increase in the order parameter,the fermion condensation in the unquenched approximation decreases when 0≤ξ5,while it increases when ξ5.However,nothing like this is observed in the quenched approximation,which indicates that there may be flaws in the quenched approximations.展开更多
Due to the negligible non-perturbation effect in the low-energy region, quantum chromodynamics （QCD） is limited to be applied to hadron problems in particle physics. However, QED has mature non-perturbation models w...Due to the negligible non-perturbation effect in the low-energy region, quantum chromodynamics （QCD） is limited to be applied to hadron problems in particle physics. However, QED has mature non-perturbation models which can be applied to Fermi acting-energy between quark and gluon. This paper applies quantum electrodynamics in 2 ＋ 1 dimensions （QED3） to the Fermi condensation problems. First, the Dyson-Schwinger equation which the fermions satisfy is constructed, and then the Fermi energy gap is solved. Theoretical calculations show that within the chirality limit, there exist three solutions for the energy gap; beyond the chirality limit, there are two solutions; all these solutions correspond to different fermion condensates. It can be concluded that the fermion condensates within the chirality limit can be used to analyze the existence of antiferromagnetic, pseudogap, and superconducting phases, and two fermion condensates are discovered beyond the chirality limit.展开更多
基金The Science Foundation of Southeast University,the National Natural Science Foundation of China (No. 11047005)
文摘Based on three-dimensional quantum electrodynamics theory,a set of truncated Dyson-Schwinger（D-S） equations are solved to study photon and fermion propagators with the effect of vacuum polarization.Numerical studies show that condensation and the value of fermion mass depends heavily on how the D-S equations are truncated.By solving a set of coupled D-S equations,it is also found that the fermion propagator shows a clear dependence on the order parameter.The truncated D-S equations under unquenched approximation are used to study the mass-function and chiral condensation of the fermions.The results under the unquenched approximation are clearly different from the ones under quenched approximation.With the increase in the order parameter,the fermion condensation in the unquenched approximation decreases when 0≤ξ5,while it increases when ξ5.However,nothing like this is observed in the quenched approximation,which indicates that there may be flaws in the quenched approximations.
基金The National Natural Science Foundation of China(No.11047005)the Science Foundation of Southeast University
文摘Due to the negligible non-perturbation effect in the low-energy region, quantum chromodynamics （QCD） is limited to be applied to hadron problems in particle physics. However, QED has mature non-perturbation models which can be applied to Fermi acting-energy between quark and gluon. This paper applies quantum electrodynamics in 2 ＋ 1 dimensions （QED3） to the Fermi condensation problems. First, the Dyson-Schwinger equation which the fermions satisfy is constructed, and then the Fermi energy gap is solved. Theoretical calculations show that within the chirality limit, there exist three solutions for the energy gap; beyond the chirality limit, there are two solutions; all these solutions correspond to different fermion condensates. It can be concluded that the fermion condensates within the chirality limit can be used to analyze the existence of antiferromagnetic, pseudogap, and superconducting phases, and two fermion condensates are discovered beyond the chirality limit.
