Author(s): Laurin E. Fischer, Daniel Bultrini, Timothée Dao, Ivano Tavernelli, and Francesco Tacchino Quantum subspace expansion (QSE) offers promising avenues to perform spectral calculations on quantum processors but comes with a large measurement overhead. Informationally complete measurements, such as classical shadows, were recently proposed to overcome this bottleneck. Here, we report the firs… [Phys. Rev. Lett. 137, 160602] Published Thu Oct 15, 2026