This quantum chemistry study investigates the first singlet (S1) and triplet (T1) excited states of phenylsulfonyl-carbazole compounds, promising thermally activated delayed fluorescence (TADF) emitters for organic light-emitting diodes (OLEDs). The quantum Equation-of-Motion Variational Quantum Eigensolver (qEOM-VQE) and Variational Quantum Deflation (VQD) algorithms were used on quantum simulators and devices with double zeta basis sets on an active space encompassing the HOMO and LUMO. Quantum simulator results for the S1-T1 energy separation (ΔEST) showed excellent agreement with experimental data. Error mitigation techniques, particularly state tomography, significantly improved the accuracy of quantum device simulations, minimizing discrepancies with exact energies. The findings demonstrate the potential of quantum computing for predicting ΔEST and other TADF properties.

Qi Gao, Gavin O. Jones, Mario Motta, Michihiko Sugawara, Hiroshi C. Watanabe, Takao Kobayashi, Eriko Watanabe, Yu-ya Ohnishi, Hajime Nakamura, Naoki Yamamoto