Ishii Wataru, Fuki Masaaki, Bu Ali Eman M, Sato Shunsuke, Parmar Bhavesh, Yamauchi Akio, Mulyadi Catherine Helenna, Uji Masanori, Medina Rivero Samara, Watanabe Go, Clark Jenny, Kobori Yasuhiro, Yanai Nobuhiro
Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
Molecular Photoscience Research Center, Kobe University, 1-1, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan.
J Am Chem Soc. 2024 Sep 18;146(37):25527-25535. doi: 10.1021/jacs.4c05677. Epub 2024 Sep 9.
Singlet fission (SF) is a promising approach in quantum information science because it can generate spin-entangled quintet triplet pairs by photoexcitation independent of temperature. However, it is still challenging to rationally achieve quantum coherence at room temperature, which requires precise control of the orientation and dynamics of triplet pairs. Here we show that the quantum coherence of quintet multiexcitons can be achieved at room temperature by arranging two pentacene chromophores in parallel and in close proximity within a macrocycle. By making dynamic covalent Schiff-base bonds between aldehyde-modified pentacene derivatives, macrocyclic parallel dimer-1 () can be selectively synthesized in a high yield. exhibits fast subpicosecond SF in polystyrene film and generates spin-polarized quintet multiexcitons. Furthermore, the coherence time of the quintet is as long as 648 ns, even at room temperature. This macrocyclic parallel dimer strategy opens up new possibilities for future quantum applications using molecular multilevel qubits.
单重态裂变（SF）是量子信息科学中一种很有前景的方法，因为它可以通过光激发产生自旋纠缠的五重态-三重态对，且与温度无关。然而，在室温下合理地实现量子相干仍然具有挑战性，这需要精确控制三重态对的取向和动力学。在这里，我们表明，通过在大环内将两个并五苯发色团平行且紧密排列，可以在室温下实现五重态多激子的量子相干。通过在醛修饰的并五苯衍生物之间形成动态共价席夫碱键，可以高产率地选择性合成大环平行二聚体-1（）。在聚苯乙烯薄膜中表现出快速的亚皮秒级单重态裂变，并产生自旋极化的五重态多激子。此外，即使在室温下，五重态的相干时间也长达648纳秒。这种大环平行二聚体策略为未来使用分子多能级量子比特的量子应用开辟了新的可能性。
