Ab initio quantum simulation of strongly correlated materials with quantum embedding

Quantum computing has shown great potential in various quantum chemical applications such as drug discovery,material design,and catalyst optimization.Although significant progress has been made in the quantum simulation of simple molecules,ab initio simulation of solid-state materials on quantum computers is still in its early stage,mostly owing to the fact that the system size quickly becomes prohibitively large when approaching the thermodynamic limit.In this work,we introduce an orbital-based multifragment approach on top of the periodic density matrix embedding theory,resulting in a significantly smaller problem size for the current near-term quantum computer.We demonstrate the accuracy and efficiency of our method compared with the conventional methodologies and experiments on solid-state systems with complex electronic structures.These include spin-polarized states of a hydrogen chain(1D-H),the equation of state of a boron nitride layer(h-BN)as well as the magnetic ordering in nickel oxide(NiO),a prototypical strongly correlated solid.Our results suggest that quantum embedding combined with a chemically intuitive fragmentation can greatly advance quantum simulation of realistic materials,thereby paving the way for solving important yet classically hard industrial problems on near-term quantum devices.

Impeded degradation of perovskite solar cells via the dual interfacial modification of siloxane

It is challenging to improve the long-term stability of perovskite solar cells(PSCs) without sacrificing efficiency. The perovskite absorbers degrade from the film surface/interfaces, which follows entangled mechanisms that have not been fully revealed yet.Herein, we decouple and elaborate two distinctive pathways regarding film degradation based on FACsPbI3perovskites.Moreover, a dual interfacial modification strategy has been developed for improving the material’s intrinsic stability, thus leading to the film degrading in a more retardant pathway. The corresponding PSCs achieve a stable power output efficiency of 23.75%.More importantly, the unencapsulated PSCs devices retain over 93% of their initial PCE after the maximum power point(MPP)tracking under the continuous 1-sun illumination and show significantly improved stability after aged under the thermal treatment or stored in ambient atmosphere for over 1500 hours without obvious PCE decay. This work shows the importance of modulating the degradation pathway on stability improvement, and at the same time, proposes a strategy for designing perovskite-based optoelectronics with excellent performance and stability.