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arXiv · 2210.12032

Benchmarks and results of the two-band Hubbard model from the Gutzwiller conjugate gradient minimization theory

Zhuo Ye·Feng Zhang·Yong-Xin Yao·Cai-Zhuang Wang·Kai-Ming Ho
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Abstract

Ground-state properties, such as energies and double occupancies, of a one-dimensional two-band Hubbard model are calculated using a first principles Gutzwiller conjugate gradient minimization theory. The favorable agreement with the results from the density matrix renormalization group theory demonstrates the accuracy of our method. A rotationally invariant approach is further incorporated into the method to greatly reduce the computational complexity with a speedup of 300 times. Moreover, we investigate the Mott transition between a metal and a Mott insulator by evaluating the charge gap. With greatly reduced computational effort, our method reproduces the phase diagram in reasonable agreement with the density matrix renormalization group theory.

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Zhuo Ye, Feng Zhang, Yong-Xin Yao, Cai-Zhuang Wang, Kai-Ming Ho. 2022-10-21. Benchmarks and results of the two-band Hubbard model from the Gutzwiller conjugate gradient minimization theory. https://arxiv.org/abs/2210.12032

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