Physical review. B./Physical review. B
Controllable quantum walks, gravitational constant, and Casimir energy in one-dimensional three-boson systems with on-site interactions
Hongting Yang, Pinquan Qin
Abstract
This study scrutinizes one-dimensional three-boson systems with on-site interactions, delving into perturbation theory, continuous-time quantum walks, and quantum Fisher information (QFI), among other areas. Notably, two critical on-site interaction strength points emerge. At these specific locations, the QFI reaches its zenith, exhibiting a proportionality to ${t}^{4}$. This substantively amplifies the precision in measuring both the Newtonian constant of gravitation and the E\"otv\"os parameter. The improvement surpasses models devoid of on-site interactions by 6 orders of magnitude. The methodology used to measure big $G$ can be adapted to quantify the Casimir energy of a many-particle system.