issp-center-dev / HPhi

Quantum Lattice Model Simulator Package
https://www.pasums.issp.u-tokyo.ac.jp/hphi/en/
GNU General Public License v3.0
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single-particle Green's function with Lanczos method #158

Open j-otsuki opened 3 months ago

j-otsuki commented 3 months ago

I would like to compute the single-particle Green's function and the single-particle excitation spectrum with the Lanczos method. I hope this functionality will be implemented in the future release.

It would be nice if we can compute G_{ij}(z) for arbitrary spin/orbital/site index i, j and the (imagiary) frequency z. Here, pure imaginary z corresponds to the Matsubara Green's function and real z (with infinitesimal imaginary number) corresponds to the retarded Green's function.