“…very long time dynamics and the potential is not a confinement potential in nonlinear optics [21,23], the simple boundary condition, such as homogeneous Dirichlet or Neumann or periodic boundary condition used in the previous subsections to truncate (or approximate) the original NLSE/GPE from the whole space problem to a bounded computational domain, might bring large truncation errors except that the bounded computational domain is chosen extremely large and/or time-dependent. Thus, in order to choose a smaller computational domain which might save memory and/or computational cost, perfectly matched layers (PMLs) [60] or high-order absorbing (or artificial) boundary conditions (ABCs) [12,21,23,59,102,149,154] need to be designed and/or used at the artificial boundary so that one can truncate (or approximate) the original NLSE/GPE into a smaller bounded computational domain. Over the last 20 years, different PMLs [153,195] and/or ABCs [14,15,16,17,18,19,21,23,172,171,194] have been designed for solving the NLSE/GPE in the literatures.…”