TY - UNPB
T1 - Divergences in classical and quantum linear response and equation of motion formulations
AU - Kjellgren, Erik Rosendahl
AU - Reinholdt, Peter
AU - Ziems, Karl Michael
AU - Sauer, Stephan P. A.
AU - Coriani, Sonia
AU - Kongsted, Jacob
PY - 2024/6/24
Y1 - 2024/6/24
N2 - Calculating molecular properties using quantum devices can be done through the quantum linear response (qLR) or, equivalently, the quantum equation of motion (qEOM) formulations. Different parameterizations of qLR and qEOM are available, namely naive, projected, self-consistent, and state-transfer. In the naive and projected parameterizations, the metric is not the identity, and we show that it depends on the redundant orbital rotations. This dependency may lead to divergences in the excitation energies for certain choices of the redundant orbital rotation parameters in an idealized noise-less setting. Further, this leads to significant variance when calculations include statistical noise from finite quantum sampling.
AB - Calculating molecular properties using quantum devices can be done through the quantum linear response (qLR) or, equivalently, the quantum equation of motion (qEOM) formulations. Different parameterizations of qLR and qEOM are available, namely naive, projected, self-consistent, and state-transfer. In the naive and projected parameterizations, the metric is not the identity, and we show that it depends on the redundant orbital rotations. This dependency may lead to divergences in the excitation energies for certain choices of the redundant orbital rotation parameters in an idealized noise-less setting. Further, this leads to significant variance when calculations include statistical noise from finite quantum sampling.
KW - Faculty of Science
KW - Qunatum Computing
KW - linear response theory
KW - excitation energies
U2 - 10.48550/arXiv.2406.17141
DO - 10.48550/arXiv.2406.17141
M3 - Preprint
VL - 2406.17141
BT - Divergences in classical and quantum linear response and equation of motion formulations
PB - arxiv.org
ER -