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#################################
# Domain, Resolution & Numerics
#
# time-scale with highly kinetic dynamics
stop_time = 0.2e-12 # [s]
# time-scale for converged ion energy
# notes: - effective acc. time depends on laser pulse
# - ions will start to leave the box
#stop_time = 1.0e-12 # [s]
# quick tests at ultra-low res. (CI)
#amr.n_cell = 384 512
# proper resolution for 10 n_c excl. acc. length
# (>=1x V100)
amr.n_cell = 2688 3712
# proper resolution for 30 n_c (dx<=3.33nm) incl. acc. length
# (>=6x V100)
#amr.n_cell = 7488 14720
# simulation box, no MR
# note: increase z (space & cells) for converging ion energy
amr.max_level = 0
geometry.prob_lo = -7.5e-6 -5.e-6
geometry.prob_hi = 7.5e-6 25.e-6
geometry.is_periodic = 0 0 # non-periodic (default)
# macro-particle shape
interpolation.nox = 3
interpolation.noy = 3
interpolation.noz = 3
# numerical tuning
warpx.cfl = 0.999
warpx.use_filter = 1 # bilinear current/charge filter
#################################
# Performance Tuning
#
# simple tuning:
# the numprocs product must be equal to the number of MPI ranks and splits
# the domain on the coarsest level equally into grids;
# slicing in the 2nd dimension is preferred for ideal performance
warpx.numprocs = 1 2 # 2 MPI ranks
#warpx.numprocs = 1 4 # 4 MPI ranks
# detail tuning instead of warpx.numprocs:
# It is important to have enough cells in a block & grid, otherwise
# performance will suffer.
# Use larger values for GPUs, try to fill a GPU well with memory and place
# few large grids on each device (you can go as low as 1 large grid / device
# if you do not need load balancing).
# Slicing in the 2nd dimension is preferred for ideal performance
#amr.blocking_factor = 64
#amr.max_grid_size_x = 2688
#amr.max_grid_size_y = 128 # this is confusingly named and means z in 2D
# load balancing
# The grid & block parameters above are needed for load balancing:
# an average of ~10 grids per MPI rank (and device) are a good granularity
# to allow efficient load-balancing as the simulation evolves
algo.load_balance_intervals = 10
algo.load_balance_costs_update = Heuristic
# particle bin-sorting on GPU (ideal defaults not investigated in 2D)
# Try larger values than the defaults below and report back! :)
#warpx.sort_intervals = 4 # default on CPU: -1 (off); on GPU: 4
#warpx.sort_bin_size = 1 1 1
#################################
# Target Profile
#
particles.species_names = electrons hydrogen
# particle species
hydrogen.species_type = hydrogen
hydrogen.injection_style = NUniformPerCell
hydrogen.num_particles_per_cell_each_dim = 2 2 4
hydrogen.momentum_distribution_type = constant
hydrogen.ux = 0.0
hydrogen.uy = 0.0
hydrogen.uz = 0.0
#hydrogen.zmin = -10.0e-6
#hydrogen.zmax = 10.0e-6
hydrogen.profile = parse_density_function
electrons.species_type = electron
electrons.injection_style = NUniformPerCell
electrons.num_particles_per_cell_each_dim = 2 2 4
electrons.momentum_distribution_type = "gaussian"
electrons.ux_th = .01
electrons.uz_th = .01
#electrons.zmin = -10.0e-6
#electrons.zmax = 10.0e-6
# ionization physics (field ionization/ADK)
# [i1] none (fully pre-ionized):
electrons.profile = parse_density_function
# [i2] field ionization (ADK):
#hydrogen.do_field_ionization = 1
#hydrogen.physical_element = H
#hydrogen.ionization_initial_level = 0
#hydrogen.ionization_product_species = electrons
#electrons.profile = constant
#electrons.density = 0.0
# collisional physics (binary MC model after Nanbu/Perez)
#collisions.collision_names = c_eH c_ee c_HH
#c_eH.species = electrons hydrogen
#c_ee.species = electrons electrons
#c_HH.species = hydrogen hydrogen
#c_eH.CoulombLog = 15.9
#c_ee.CoulombLog = 15.9
#c_HH.CoulombLog = 15.9
# number density: "fully ionized" electron density as reference
# [material 1] cryogenic H2
my_constants.nc = 1.742e27 # [m^-3] 1.11485e21 * 1.e6 / 0.8**2
my_constants.n0 = 30.0 # [n_c]
# [material 2] liquid crystal
#my_constants.n0 = 192
# [material 3] PMMA
#my_constants.n0 = 230
# [material 4] Copper (ion density: 8.49e28/m^3; times ionization level)
#my_constants.n0 = 1400
# profiles
# pre-plasma
my_constants.L = 0.05e-6 # [1/m] scale length (>0)
my_constants.Lcut = 2.0e-6 # [1/m] hard cutoff from surface
# core: flat foil, cylinder or sphere
my_constants.r0 = 2.5e-6 # [m] radius or half-thickness
# [target 1] flat foil (thickness = 2*r0)
electrons.density_function(x,y,z) = "nc*n0*(
(abs(z)<=r0) +
(abs(z)>r0)*(abs(z)<r0+Lcut)*exp( (-abs(z)+r0)/L ) )"
hydrogen.density_function(x,y,z) = "nc*n0*(
(abs(z)<=r0) +
(abs(z)>r0)*(abs(z)<r0+Lcut)*exp( (-abs(z)+r0)/L ) )"
# [target 2] cylinder
#electrons.density_function(x,y,z) = "nc*n0*(
# ((x*x+z*z)<=(r0*r0)) +
# (sqrt(x*x+z*z)>r0)*(sqrt(x*x+z*z)<r0+Lcut)*exp( (-sqrt(x*x+z*z)+r0)/L ) )"
#hydrogen.density_function(x,y,z) = "nc*n0*(
# ((x*x+z*z)<=(r0*r0)) +
# (sqrt(x*x+z*z)>r0)*(sqrt(x*x+z*z)<r0+Lcut)*exp( (-sqrt(x*x+z*z)+r0)/L ) )"
# [target 3] sphere
#electrons.density_function(x,y,z) = "nc*n0*(
# ((x*x+y*y+z*z)<=(r0*r0)) +
# (sqrt(x*x+y*y+z*z)>r0)*(sqrt(x*x+y*y+z*z)<r0+Lcut)*exp( (-sqrt(x*x+y*y+z*z)+r0)/L ) )"
#hydrogen.density_function(x,y,z) = "nc*n0*(
# ((x*x+y*y+z*z)<=(r0*r0)) +
# (sqrt(x*x+y*y+z*z)>r0)*(sqrt(x*x+y*y+z*z)<r0+Lcut)*exp( (-sqrt(x*x+y*y+z*z)+r0)/L ) )"
#################################
# Laser Pulse Profile
#
lasers.names = laser1
laser1.position = 0. 0. -4.0e-6 # point the laser plane (antenna)
laser1.direction = 0. 0. 1. # the plane's (antenna's) normal direction
laser1.polarization = 1. 0. 0. # the main polarization vector
laser1.a0 = 16.0 # maximum amplitude of the laser field [V/m]
laser1.wavelength = 0.8e-6 # central wavelength of the laser pulse [m]
laser1.profile = Gaussian
laser1.profile_waist = 4.e-6 # beam waist (E(w_0)=E_0/e) [m]
laser1.profile_duration = 30.e-15 # pulse length (E(tau)=E_0/e; tau=tau_E=FWHM_I/1.17741) [s]
laser1.profile_t_peak = 50.e-15 # time until peak intensity reached at the laser plane [s]
laser1.profile_focal_distance = 4.0e-6 # focal distance from the antenna [m]
# e_max = a0 * 3.211e12 / lambda_0[mu]
# a0 = 16, lambda_0 = 0.8mu -> e_max = 64.22 TV/m
#################################
# Diagnostics
#
diagnostics.diags_names = diag1 openPMDfw openPMDbw
diag1.intervals = 100
diag1.diag_type = Full
diag1.fields_to_plot = Ex Ey Ez Bx By Bz jx jy jz rho rho_electrons rho_hydrogen
# reduce resolution of output fields
diag1.coarsening_ratio = 4 4
diag1.electrons.variables = w ux uy uz
diag1.hydrogen.variables = w ux uy uz
# demonstration of a spatial and momentum filter
diag1.electrons.plot_filter_function(t,x,y,z,ux,uy,uz) = (uz>=0) * (x<1.0e-6) * (x>-1.0e-6)
diag1.hydrogen.plot_filter_function(t,x,y,z,ux,uy,uz) = (uz>=0) * (x<1.0e-6) * (x>-1.0e-6)
openPMDfw.intervals = 100
openPMDfw.diag_type = Full
openPMDfw.fields_to_plot = Ex Ey Ez Bx By Bz jx jy jz rho rho_electrons rho_hydrogen
# reduce resolution of output fields
openPMDfw.coarsening_ratio = 4 4
openPMDfw.electrons.variables = w ux uy uz
openPMDfw.hydrogen.variables = w ux uy uz
openPMDfw.format = openpmd
openPMDfw.openpmd_backend = h5
openPMDfw.species = electrons hydrogen
# demonstration of a spatial and momentum filter
openPMDfw.electrons.plot_filter_function(t,x,y,z,ux,uy,uz) = (uz>=0) * (x<1.0e-6) * (x>-1.0e-6)
openPMDfw.hydrogen.plot_filter_function(t,x,y,z,ux,uy,uz) = (uz>=0) * (x<1.0e-6) * (x>-1.0e-6)
openPMDbw.intervals = 100
openPMDbw.diag_type = Full
openPMDbw.fields_to_plot = rho_hydrogen
# reduce resolution of output fields
openPMDbw.coarsening_ratio = 4 4
openPMDbw.electrons.variables = w ux uy uz
openPMDbw.hydrogen.variables = w ux uy uz
openPMDbw.format = openpmd
openPMDbw.openpmd_backend = h5
openPMDbw.species = electrons hydrogen
# demonstration of a momentum filter
openPMDbw.electrons.plot_filter_function(t,x,y,z,ux,uy,uz) = (uz<0)
openPMDbw.hydrogen.plot_filter_function(t,x,y,z,ux,uy,uz) = (uz<0)
#################################
# Reduced Diagnostics
#
# histograms with 2.0 degree acceptance angle in fw direction
# 2 deg * pi / 180 : 0.03490658503 rad
# half-angle +/- : 0.017453292515 rad
warpx.reduced_diags_names = histuH histue histuzAll
histuH.type = ParticleHistogram
histuH.intervals = 100
histuH.path = "./"
histuH.species = hydrogen
histuH.bin_number = 1000
histuH.bin_min = 0.0
histuH.bin_max = 35.0
histuH.histogram_function(t,x,y,z,ux,uy,uz) = "sqrt(ux*ux+uy*uy+uz*uz)"
histuH.filter_function(t,x,y,z,ux,uy,uz) = "abs(acos(uz / sqrt(ux*ux+uy*uy+uz*uz))) <= 0.017453"
histue.type = ParticleHistogram
histue.intervals = 100
histue.path = "./"
histue.species = electrons
histue.bin_number = 1000
histue.bin_min = 0.0
histue.bin_max = 0.1
histue.histogram_function(t,x,y,z,ux,uy,uz) = "sqrt(ux*ux+uy*uy+uz*uz)"
histue.filter_function(t,x,y,z,ux,uy,uz) = "abs(acos(uz / sqrt(ux*ux+uy*uy+uz*uz))) <= 0.017453"
# just a test entry to make sure that the histogram filter is purely optional:
# this one just records uz of all hydrogen ions, independent of their pointing
histuzAll.type = ParticleHistogram
histuzAll.intervals = 100
histuzAll.path = "./"
histuzAll.species = hydrogen
histuzAll.bin_number = 1000
histuzAll.bin_min = -35.0
histuzAll.bin_max = 35.0
histuzAll.histogram_function(t,x,y,z,ux,uy,uz) = "uz"
#################################
# Physical Background
#
# This example is modeled after a target similar to the hydrogen jet here:
# [1] https://doi.org/10.1038/s41598-017-10589-3
# [2] https://arxiv.org/abs/1903.06428
#
authors = "Axel Huebl <axelhuebl@lbl.gov>"
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