Major updateUpdate (Jan. 2023): new record, andrecord; new hope!?
A new approach to factoring using quantum computers has recently been proposed: Bao Yan, Ziqi Tan, Shijie Wei, Haocong Jiang, Weilong Wang, Hong Wang, Lan Luo, Qianheng Duan, Yiting Liu, Wenhao Shi, Yangyang Fei, Xiangdong Meng, Yu Han, Zheng Shan, Jiachen Chen, Xuhao Zhu, Chuanyu Zhang, Feitong Jin, Hekang Li, Chao Song, Zhen Wang, Zhi Ma, H. Wang, Gui-Lu Long, Factoring integers with sublinear resources on a superconducting quantum processor (arXiv.2212.12372). They report factoring any 48-bit integer, including experimentally factoring 261980999226229=15538213×16860433 with help of a 10-bit quantum computer, by an algorithm which required number of qbits is nearly linear (even slightly sub-linear) with the bit size of the integer factored. They perform on a quantum computer the hard part (a Short Vector Problem) of some known factorization method. The approach seems interesting. It'sis discussed here.