Huijse Liza, Bauer Bela, Berg Erez
Stanford Institute for Theoretical Physics, Stanford University, Stanford, California 94305, USA.
Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Phys Rev Lett. 2015 Mar 6;114(9):090404. doi: 10.1103/PhysRevLett.114.090404.
We show that supersymmetry emerges in a large class of models in 1+1 dimensions with both Z_{2} and U(1) symmetry at the multicritical point where the Ising and Berezinskii-Kosterlitz-Thouless transitions coincide. To arrive at this result we perform a detailed renormalization group analysis of the multicritical theory including all perturbations allowed by symmetry. This analysis reveals an intricate flow with a marginally irrelevant direction that preserves part of the supersymmetry of the fixed point. The slow flow along this special line has significant consequences on the physics of the multicritical point. In particular, we show that the scaling of the U(1) gap away from the multicritical point is different from the usual Berezinskii-Kosterlitz-Thouless exponential gap scaling.
我们证明，在1 + 1维的一大类模型中，在伊辛（Ising）转变和贝雷津斯基 - 科斯特利茨 - Thouless（Berezinskii-Kosterlitz-Thouless）转变重合的多临界点处，超对称性在具有(Z_{2})和(U(1))对称性的情况下出现。为了得到这个结果，我们对多临界理论进行了详细的重整化群分析，包括对称性允许的所有微扰。该分析揭示了一个复杂的流，其具有一个边缘无关方向，该方向保留了不动点的部分超对称性。沿着这条特殊线的缓慢流动对多临界点的物理性质有重大影响。特别是，我们表明远离多临界点时(U(1))能隙的标度不同于通常的贝雷津斯基 - 科斯特利茨 - Thouless指数能隙标度。
