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Density matrix renormalization group in a two-dimensional $λϕ^4$ Hamiltonian lattice model

Takanori Sugihara
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Abstract

Density matrix renormalization group (DMRG) is applied to a (1+1)-dimensional $λϕ^4$ model. Spontaneous breakdown of discrete $Z_2$ symmetry is studied numerically using vacuum wavefunctions. We obtain the critical coupling $(λ/μ^2)_{\rm c}=59.89\pm 0.01$ and the critical exponent $β=0.1264\pm 0.0073$, which are consistent with the Monte Carlo and the exact results, respectively. The results are based on extrapolation to the continuum limit with lattice sizes $L=250,500$, and 1000. We show that the lattice size L=500 is sufficiently close to the the limit $L\to\infty$.

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Takanori Sugihara. 2004-04-30. Density matrix renormalization group in a two-dimensional $λϕ^4$ Hamiltonian lattice model. https://doi.org/10.1088/1126-6708%2F2004%2F05%2F007

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