Merge pull request LupoLab#359 from chrisbrahms/complex-ref-index

RFC: Complex ref index for gases

Author: chrisbrahms

src/PhysData.jl

@@ -90,7 +90,7 @@ Sellmeier expansion for linear susceptibility from Applied Optics 47, 27, 4856 (
 room temperature and atmospheric pressure
 """
 function γ_Börzsönyi(B1, C1, B2, C2)
-    return μm -> (B1 * μm^2 / (μm^2 - C1) + B2 * μm^2 / (μm^2 - C2))
+    return μm -> complex(B1 * μm^2 / (μm^2 - C1) + B2 * μm^2 / (μm^2 - C2))
 end
 
 """
@@ -100,7 +100,7 @@ Adapted Sellmeier expansion for helium made to fit high frequency data
 Phys. Rev. A 92, 033821 (2015)
 """
 function γ_JCT(B1, C1, B2, C2, B3, C3)
-    return μm -> (B1 * μm^2 / (μm^2 - C1)
+    return μm -> complex(B1 * μm^2 / (μm^2 - C1)
                   + B2 * μm^2 / (μm^2 - C2)
                   + B3 * μm^2 / (μm^2 - C3))
 end
@@ -112,7 +112,7 @@ Sellmeier expansion for linear susceptibility from
 J. Opt. Soc. Am. 67, 1550 (1977)
 """
 function γ_Peck(B1, C1, B2, C2, dens)
-    return μm -> @. (((B1 / (C1 - 1/μm^2) + B2 / (C2 - 1/μm^2)) + 1)^2 - 1)/dens
+    return μm -> complex(((B1 / (C1 - 1/μm^2) + B2 / (C2 - 1/μm^2)) + 1)^2 - 1)/dens
 end
 
 """
@@ -121,7 +121,7 @@ end
 Sellmeier expansion for Oxygen from Applied Optics 50, 35, 6484 (2011)
 """
 function γ_Zhang(A, B, C, dens)
-    return μm -> ((1 + A + B/(C-1/μm^2))^2 - 1)/dens
+    return μm -> complex((1 + A + B/(C-1/μm^2))^2 - 1)/dens
 end
 
 """
@@ -132,7 +132,7 @@ https://doi.org/10.5194/acp-21-14927-2021.
 
 """
 function γ_QuanfuHe(A, B, C, dens)
-    return μm -> ((1 + 1e-8*(A + B/(C - (1e4/μm)^2))))/dens
+    return μm -> complex((1 + 1e-8*(A + B/(C - (1e4/μm)^2))))/dens
 end
 
 """

test/test_fields.jl

@@ -405,7 +405,7 @@ end
     # test diversity of power fluctuations
     @test mean(std(Its[istart:iend,:], dims=2)[:,1]) > 10
 end
-
+##
 @testset "Propagation" begin
     λ0 = 800e-9
     τfwhm = 2.5e-15
@@ -536,8 +536,31 @@ end
         ϕs, Eωcomp = Fields.optcomp_taylor(Eωmirr, grid, λ0; order=3)
         @test isapprox(ϕs[3], -reflections*gdd, rtol=0.1)
     end
-end
 
+    # check (back-)propagation for all gases with a large grid
+    λ0 = 800e-9
+    τfwhm = 2.5e-15
+    grid = Grid.RealGrid(1, λ0, (70e-9, 4e-6), 500e-15)
+    input = Fields.GaussField(λ0=λ0, τfwhm=τfwhm, energy=1e-6)
+    x = Array{Float64}(undef, length(grid.t))
+    FT = FFTW.plan_rfft(x, 1)
+    Eω = input(grid, FT)
+    @testset "gas propgation: $g" for g in PhysData.gas
+        Eωgas = Fields.prop_material(Eω, grid, g, 10, λ0)
+        Et = FT \ Eωgas
+        gab = Maths.gabor(grid.t, Et, [-10e-15, 10e-15], 3e-15)
+        ω0 = Maths.moment(grid.ω, abs2.(gab))
+        @test ω0[1] < ω0[2]
+
+        Eωgas = Fields.prop_material(Eω, grid, g, -10, λ0)
+        Et = FT \ Eωgas
+        gab = Maths.gabor(grid.t, Et, [-10e-15, 10e-15], 3e-15)
+        ω0 = Maths.moment(grid.ω, abs2.(gab))
+        @test ω0[1] > ω0[2]
+    end
+
+end
+##
 @testset "Compression" begin
 # Short pulse with 100 fs^2
 λ0 = 800e-9