10:45
11:45

Quantum physics and chemistry have provided well-recognized theoretical tools to predict the behavior of molecules and materials described by the Schrödinger equation. However, many problems with high industrial and societal impact remain intractable for classical computers, urging us to reconsider our preconceptions and shift gears. The world of the infinitely small obeys the laws of quantum mechanics, suggesting the need for a machine governed by the same physics: this marks the birth of quantum computers, a new technological revolution which promises a quantum advantage (speed-up) over classical computers. In this talk, I will present the state-averaged orbital-optimized variational quantum eigensolver (SA-OO-VQE), designed to address the electronic structure problem for excited states [1-3], essential to unravel ubiquitous ultrafast (subpicosecond) photochemical and photophysical ‘energy/charge/matter/ information’-transfer processes induced upon the absorption of light by molecules within the UV-visible domain. I will show that SA-OO-VQE exhibits a propensity to produce an ab initio quasidiabatic representation “for free” if considered as a least-transformed block-diagonalization procedure [4]. These recent findings underscore the practical utility and potential of SA-OO-VQE for addressing systems with complex nonadiabatic phenomena.

[1] Nakanishi K. M., Mitarai K., & Fujii K. (2019). Subspace-search variational quantum eigensolver for excited states. Physical Review Research, 1(3), 033062.
[2] Yalouz S., Senjean B., Günther J., Buda F., O’Brien T. E., & Visscher L. (2021). A state-averaged orbital-optimized hybrid quantum–classical algorithm for a democratic description of ground and excited states. Quantum Science and Technology, 6(2), 024004.
[3] Yalouz S., Koridon E., Senjean B., Lasorne B., Buda F., & Visscher L. (2022). Analytical nonadiabatic couplings and gradients within the state-averaged orbital-optimized variational quantum eigensolver. Journal of chemical theory and computation, 18(2), 776-794.
[4] Illesova S., Beseda M., Yalouz S., Lasorne B., & Senjean B., to be submitted.

https://combalgo.labri.fr/pmwiki.php/Groupe/Info-Quantique

Room 178