HASEonGPU.FrozenPhiAseRungeKutta4

class HASEonGPU.FrozenPhiAseRungeKutta4

Bases: TimeIntegrationSolver

Fourth-order beta update with one frozen ASE transport solve per step.

Simulation computes the ASE flux once from the step-start beta field and reuses that fixed phiAse in all RK4 stages. Pump and local ASE coupling terms are still re-evaluated for each trial beta value. This reduces expensive ASE backend calls, but it is not identical to full RK4 of the coupled beta/ASE-transport system.

stepSimulation(simulation, betaCells, time, timeStep)

Advance one Simulation step while freezing the ASE flux.