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#!/usr/bin/env python3
#
import numpy as np
from pywarpx import picmi
#from warp import picmi
constants = picmi.constants
##########################
# physics parameters
##########################
# --- laser
laser_a0 = 4. # Normalized potential vector
laser_wavelength = 8e-07 # Wavelength of the laser (in meters)
laser_waist = 5e-06 # Waist of the laser (in meters)
laser_duration = 15e-15 # Duration of the laser (in seconds)
laser_polarization = 0. # Polarization angle (in rad)
laser_injection_loc = 9.e-6 # Position of injection (in meters, along z)
laser_focal_distance = 100.e-6 # Focal distance from the injection (in meters)
laser_t_peak = 30.e-15 # The time at which the laser reaches its peak
# at the antenna injection location (in seconds)
# --- plasma
plasma_density = 1.e24
plasma_min = [-20.e-6, -20.e-6, 0.0e-6]
plasma_max = [ 20.e-6, 20.e-6, 1.e-3]
##########################
# numerics parameters
##########################
# --- Nb time steps
max_steps = 10
# --- grid
nx = 64
ny = 64
nz = 480
xmin = 1.5*plasma_min[0]
xmax = 1.5*plasma_max[0]
ymin = 1.5*plasma_min[1]
ymax = 1.5*plasma_max[1]
zmin = -56.e-6
zmax = 12.e-6
moving_window_velocity = [0., 0., constants.c]
number_per_cell_each_dim = [2, 2, 1]
##########################
# physics components
##########################
# --- laser
laser = picmi.GaussianLaser(wavelength = laser_wavelength,
waist = laser_waist,
duration = laser_duration,
focal_position = [0., 0., laser_focal_distance + laser_injection_loc],
centroid_position = [0., 0., laser_injection_loc - constants.c*laser_t_peak],
polarization_direction = [np.cos(laser_polarization), np.sin(laser_polarization), 0.],
propagation_direction = [0,0,1],
E0 = laser_a0*2.*np.pi*constants.m_e*constants.c**2/(constants.q_e*laser_wavelength)) # Maximum amplitude of the laser field (in V/m)
laser_antenna = picmi.LaserAntenna(position = [0., 0., laser_injection_loc], # This point is on the laser plane
normal_vector = [0., 0., 1.]) # The plane normal direction
# --- plasma
uniform_plasma = picmi.UniformDistribution(density = plasma_density,
lower_bound = plasma_min,
upper_bound = plasma_max,
fill_in = True)
electrons = picmi.Species(particle_type = 'electron',
name = 'electrons',
initial_distribution = uniform_plasma)
##########################
# numerics components
##########################
grid = picmi.Cartesian3DGrid(number_of_cells = [nx, ny, nz],
lower_bound = [xmin, ymin, zmin],
upper_bound = [xmax, ymax, zmax],
lower_boundary_conditions = ['periodic', 'periodic', 'open'],
upper_boundary_conditions = ['periodic', 'periodic', 'open'],
lower_boundary_conditions_particles = ['periodic', 'periodic', 'absorbing'],
upper_boundary_conditions_particles = ['periodic', 'periodic', 'absorbing'],
moving_window_velocity = moving_window_velocity,
warpx_max_grid_size=32)
solver = picmi.ElectromagneticSolver(grid=grid, method='CKC', cfl=1.)
##########################
# diagnostics
##########################
diag_field_list = ["rho", "E", "B", "J"]
field_diag1 = picmi.FieldDiagnostic(name = 'diag1',
grid = grid,
period = 10,
write_dir = '.',
warpx_file_prefix = 'Python_LaserAccelerationMR_plt',
data_list = diag_field_list)
part_diag1 = picmi.ParticleDiagnostic(name = 'diag1',
period = 10,
species = [electrons])
##########################
# simulation setup
##########################
sim = picmi.Simulation(solver = solver,
max_steps = max_steps,
verbose = 1,
warpx_current_deposition_algo = 'esirkepov',
warpx_use_filter = 0)
sim.add_species(electrons, layout=picmi.GriddedLayout(grid=grid, n_macroparticle_per_cell=number_per_cell_each_dim))
sim.add_laser(laser, injection_method=laser_antenna)
sim.add_diagnostic(field_diag1)
sim.add_diagnostic(part_diag1)
##########################
# simulation run
##########################
# write_inputs will create an inputs file that can be used to run
# with the compiled version.
#sim.write_input_file(file_name = 'inputs_from_PICMI')
# Alternatively, sim.step will run WarpX, controlling it from Python
sim.step(max_steps)
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