Catapulting towards massive and large spatial quantum superposition

Large spatial quantum superposition of size ${\cal O}(1-10)~{\rm \mu \text{m}}$ for mass $m \sim 10^{-17}-10^{-14}~\text{kg}$ is required to probe the foundations mechanics and testing classical nature gravity via entanglement in a laboratory. In this paper, we will show that it possible accelerate two spin states macroscopic nano-crystal sourced by inhomogeneous nonlinear magnetic field Stern-Gerlach type setup. We assume electronic can be embedded at centre nano-crystal, such as nitrogen-vacancy (NV) diamond. Our analysis generic any dopant or material. create desired within $1-2$ seconds catapulting trajectories with modest gradient then recombine coherent interference. demanding precision recover $99\%$ coherence confidence level moment