Critical behavior of the (2+1)-dimensional Thirring model
Critical behavior of the (2+1)-dimensional Thirring model
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DOI：
10.1103/physrevd.86.105007
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发表时间：
2012-08
影响因子：
5
通讯作者：
L. Janssen;H. Gies
中科院分区：
文献类型：
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作者：
L. Janssen;H. Gies
借助于泛函重整化群，我们研究了（2+1）维Thirring模型中手征对称性破缺随耦合和Dirac味数Nf的变化.对于足够小的味数Nf < Nfc，该模型表现出足够大的耦合的手征量子相变。我们计算临界指数的第二阶过渡，以及费米子和玻色子的质量谱内的破相下一个领先的阶导数展开。我们还确定了由于矢量和手征标量通道之间的竞争而产生的多味跃迁的量子临界行为，这也是二阶的。由于竞争通道的问题，我们的结果依赖于RG技术的动态玻色子。对于临界风味数，我们发现Nfc ~ 5.1，估计系统误差约为一种风味。
We investigate chiral symmetry breaking in the (2+1)-dimensional Thirring model as a function of the coupling as well as the Dirac flavor number Nf with the aid of the functional renormalization group. For small enough flavor number Nf < Nfc, the model exhibits a chiral quantum phase transition for sufficiently large coupling. We compute the critical exponents of this second order transition as well as the fermionic and bosonic mass spectrum inside the broken phase within a next-to-leading order derivative expansion. We also determine the quantum critical behavior of the many-flavor transition which arises due to a competition between vector and chiral-scalar channel and which is of second order as well. Due to the problem of competing channels, our results rely crucially on the RG technique of dynamical bosonization. For the critical flavor number, we find Nfc ~ 5.1 with an estimated systematic error of approximately one flavor.