# Construction of Green's functions on a quantum computer: Quasiparticle spectra of molecules

@article{Kosugi2019ConstructionOG, title={Construction of Green's functions on a quantum computer: Quasiparticle spectra of molecules}, author={Taichi Kosugi and Yu-ichiro Matsushita}, journal={Physical Review A}, year={2019} }

We propose a scheme for the construction of the one-particle Green's function (GF) of an interacting electronic system via statistical sampling on a quantum computer. Although the nonunitarity of creation and annihilation operators for the electronic spin orbitals prevents us from preparing specific states selectively, probabilistic state preparation is demonstrated to be possible for the qubits. We provide quantum circuits equipped with at most two ancillary qubits for obtaining all the…

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