<?xml version="1.0" encoding="UTF-8"?> <simulation xmds-version="2"> <name>tla</name> <author>Unknown</author> <description> Two level atom example simulation. Illustrates a cross-propagating field. </description> <features> <benchmark /> <error_check /> <bing /> <fftw plan="patient" /> <globals> <![CDATA[ const real g = 1.0; const real t0 = 1.0; ]]> </globals> </features> <geometry> <propagation_dimension> z </propagation_dimension> <transverse_dimensions> <dimension name="t" lattice="10000" domain="(-10, 15)" /> </transverse_dimensions> </geometry> <vector name="main" initial_basis="t" type="real"> <components> E </components> <initialisation> <![CDATA[ E = 2/t0/cosh(t/t0); ]]> </initialisation> </vector> <vector name="cross" initial_basis="t" type="real"> <components> P N </components> <initialisation> <![CDATA[ P = 0.0; N = -1.0; ]]> </initialisation> </vector> <sequence> <integrate algorithm="RK4" interval="4" steps="200"> <samples>100 100</samples> <operators> <operator kind="cross_propagation" algorithm="RK4" propagation_dimension="t"> <integration_vectors>cross</integration_vectors> <!-- You can have a dependencies tag in here --> <dependencies>main</dependencies> <boundary_condition kind="left"> <!-- You can also have a dependencies tag in here --> <!-- like the one shown below, but none are needed --> <!-- in this example --> <!-- <dependencies>cross</dependencies> --> <![CDATA[ P = 0.0; N = -1.0; ]]> </boundary_condition> <![CDATA[ dP_dt = E*N; dN_dt = -E*P; ]]> </operator> <integration_vectors>main</integration_vectors> <![CDATA[ dE_dz = g*P; ]]> </operators> </integrate> </sequence> <output> <sampling_group basis="t(1000)" initial_sample="yes"> <moments>pow_dens</moments> <dependencies>main</dependencies> <![CDATA[ pow_dens = E*E; ]]> </sampling_group> <sampling_group basis="t(1000)" initial_sample="no"> <moments>P_out N_out</moments> <dependencies>cross</dependencies> <![CDATA[ P_out = P; N_out = N; ]]> </sampling_group> </output> </simulation>