Quantum-electrodynamical time-dependent density functional theory within Gaussian atomic basis

Junjie Yang; Qi Ou; Zheng Pei; Hua Wang; Binbin Weng; Zhigang Shuai; Kieran Mullen; Yihan Shao

doi:10.1063/5.0057542

Quantum-electrodynamical time-dependent density functional theory within Gaussian atomic basis

J Chem Phys. 2021 Aug 14;155(6):064107. doi: 10.1063/5.0057542.

Authors

Junjie Yang¹, Qi Ou², Zheng Pei³, Hua Wang⁴, Binbin Weng⁵, Zhigang Shuai², Kieran Mullen⁴, Yihan Shao¹

Affiliations

¹ Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, USA.
² MOE Key Laboratory of Organic OptoElectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing 100084, China.
³ State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China.
⁴ Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, Oklahoma 73019, USA.
⁵ Microfabrication Research and Education Center and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019, USA.

Abstract

Inspired by the formulation of quantum-electrodynamical time-dependent density functional theory (QED-TDDFT) by Rubio and co-workers [Flick et al., ACS Photonics 6, 2757-2778 (2019)], we propose an implementation that uses dimensionless amplitudes for describing the photonic contributions to QED-TDDFT electron-photon eigenstates. This leads to a Hermitian QED-TDDFT coupling matrix that is expected to facilitate the future development of analytic derivatives. Through a Gaussian atomic basis implementation of the QED-TDDFT method, we examined the effect of dipole self-energy, rotating-wave approximation, and the Tamm-Dancoff approximation on the QED-TDDFT eigenstates of model compounds (ethene, formaldehyde, and benzaldehyde) in an optical cavity. We highlight, in the strong coupling regime, the role of higher-energy and off-resonance excited states with large transition dipole moments in the direction of the photonic field, which are automatically accounted for in our QED-TDDFT calculations and might substantially affect the energies and compositions of polaritons associated with lower-energy electronic states.

Grants and funding

R01 GM135392/GM/NIGMS NIH HHS/United States