Fig. 9: Monte-Carlo trajectory based simulations for the strong-correlated H4 molecule in STO-3G at different bond lengths.
From: Dissipative ground state preparation in ab initio electronic structure theory
a The accuracy of the HF, CCSD and CCSD(T) energy and the initial overlap between the HF state and the true ground state ρg at different bond lengths for square H4 system in STO-3G. The green, yellow, and purple lines show the energy errors from HF, CCSD, and CCSD(T), respectively; the blue line shows the initial overlap, and the red dashed line marks chemical accuracy. b The energy error relative to FCI energy vs. Lindblad simulation time at bond lengths d = 1.2, 1.4, 1.6, and 2.0 Å. The solid lines (blue, orange, green, red) represent Lindblad dynamics at bond lengths d = 1.2, 1.4, 1.6, and 2.0 Å; the red dotted line indicates chemical accuracy, and the dashed lines show the fitting. c The spectral gaps of the Lindbladian \({\mathcal{L}}\) and the Hamiltonian at bond lengths d = 1.2, 1.4, 1.6 and 2.0 Å. The blue line denotes the Lindbladian gap \({\Delta }_{{\mathcal{L}}}\), while the orange line denotes the Hamiltonian gap \({\Delta }_{\hat{H}}\).
