标题： 一维相对论场论的三临界行为 显示英文标题

标题： Tricritical behavior of a relativistic field theory in one dimension

摘要： 分析了一类一维（1D）场论在零温及零化学势下表现出自发对称破缺行为的三临界现象。在无质量费米子的Gross-Neveu（GN）型模型中，离散手征对称性被自发破缺。掺杂后，在临界化学势下对称性得以恢复。我们研究了在外加恒定Zeeman磁场 $B_0$ 下，这种掺杂的一维系统的温度效应。我们发现 $B_0$ 抑制了某些化学势值下的无能隙行为，并能在临界场强下诱导出无能隙-有能隙相变。此外，我们还讨论了在Ginzburg-Landau展开中考虑非均匀凝聚态对三临界点的影响。 显示英文摘要

摘要： The tricritical behavior in a class of one-dimensional (1D) field theories that exhibit spontaneous symmetry breaking at zero temperature and chemical potential is analyzed. In the Gross-Neveu (GN)-type models of massless fermions the discrete chiral symmetry is spontaneously broken. After doping, the symmetry is restored at a critical chemical potential. We investigate the temperature effects on this doped 1D system under an external constant Zeeman magnetic field $B_0$. We find that $B_0$ suppresses the gapless behavior present for certain values of chemical potential and is able to induce a gapless-gapped phase transition at a critical field strength. We also discuss about the consequences of the consideration of inhomogeneous condensates to the tricritical point, within the Ginzburg-Landau expansion.