### Off-Specular scattering

Off-specular scattering from a monodisperse distribution of long boxes.

• The sample is made of very long boxes with length equal to $1000$ nm, width $20$ nm and height $10$ nm.
• The particles are distributed along a one-dimensional lattice with a lattice spacing of $100$ nm in the $x$-direction.
• The particles are rotated around the $z$-axis by $90^{\circ}$ so that their “infinite” dimension is parallel to the $y$-direction.
• The incident wavelength is equal to 0.1 nm.
• The output intensity is the result of an average over $\varphi_i$ comprised between $-1^{\circ}$ and $1^{\circ}$ and of a scan of $\alpha_i$ and $\alpha_f$ between $0^{\circ}$ and $10^{\circ}$.

Note:

The two-dimensional output intensity is plotted as a function of $\alpha_i$ and $\alpha_f$.

  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79  #!/usr/bin/env python3 """ Long boxes at 1D lattice, ba.Offspec simulation """ import bornagain as ba from bornagain import ba_plot as bp, deg, nm phi_f_min, phi_f_max = -1, 1.0 alpha_f_min, alpha_f_max = 0, 10.0 alpha_i_min, alpha_i_max = 0, 10.0 # incoming beam def get_sample(): """ Returns a sample with a grating on a substrate, modelled by infinitely long boxes forming a 1D lattice. """ # Define materials material_Particle = ba.RefractiveMaterial("Particle", 0.0006, 2e-08) material_Substrate = ba.RefractiveMaterial("Substrate", 6e-06, 2e-08) material_Vacuum = ba.RefractiveMaterial("Vacuum", 0, 0) # Define form factors ff = ba.Box(1000*nm, 20*nm, 10*nm) # Define particles particle = ba.Particle(material_Particle, ff) particle_rotation = ba.RotationZ(90*deg) particle.rotate(particle_rotation) # Define interference functions iff = ba.Interference1DLattice(100*nm, 0) iff_pdf = ba.Profile1DCauchy(1e6*nm) iff.setDecayFunction(iff_pdf) # Define particle layouts layout = ba.ParticleLayout() layout.addParticle(particle) layout.setInterference(iff) layout.setTotalParticleSurfaceDensity(0.01) # Define layers layer_1 = ba.Layer(material_Vacuum) layer_1.addLayout(layout) layer_2 = ba.Layer(material_Substrate) # Define sample sample = ba.MultiLayer() sample.addLayer(layer_1) sample.addLayer(layer_2) return sample def get_simulation(sample): """ Returns an off-specular simulation with beam and detector defined. """ n = bp.simargs['n'] simulation = ba.OffspecSimulation(sample) simulation.detector().setDetectorParameters(20, phi_f_min*deg, phi_f_max*deg, n, alpha_f_min*deg, alpha_f_max*deg) # define the beam with alpha_i varied between alpha_i_min and alpha_i_max alpha_i_axis = ba.FixedBinAxis("alpha_i", n, alpha_i_min*deg, alpha_i_max*deg) simulation.setBeamParameters(0.1*nm, alpha_i_axis, 0) simulation.beam().setIntensity(1e9) return simulation if __name__ == '__main__': bp.parse_args(sim_n=200, intensity_min=1) sample = get_sample() simulation = get_simulation(sample) result = simulation.simulate() bp.plot_simulation_result(result) 
Examples/varia/OffspecSimulation.py