Room-temperature quantum coherence of entangled multiexcitons in a metal-organic framework
Akio Yamauchi, Kentaro TANAKA, Masaaki Fuki, Saiya Fujiwara, Nobuo Kimizuka, Tomohiro Ryu, Masaki Saigo, Ken Onda, Ryota Kusumoto, Nami Ueno, Harumi Sato, Yasuhiro Kobori, Kiyoshi Miyata, Nobuhiro Yanai
Abstract
Singlet fission can generate an exchange-coupled quintet triplet pair state 5 TT, which could lead to the realization of quantum computing and quantum sensing using entangled multiple qubits even at room temperature. However, the observation of the quantum coherence of 5 TT has been limited to cryogenic temperatures, and the fundamental question is what kind of material design will enable its room-temperature quantum coherence. Here, we show that the quantum coherence of singlet fission–derived 5 TT in a chromophore-integrated metal-organic framework can be over hundred nanoseconds at room temperature. The suppressed motion of the chromophores in ordered domains within the metal-organic framework leads to the enough fluctuation of the exchange interaction necessary for 5 TT generation but, at the same time, does not cause severe 5 TT decoherence. Furthermore, the phase and amplitude of quantum beating depend on the molecular motion, opening the way to room-temperature molecular quantum computing based on multiple quantum gate control.