Title:
Tutorial example - 1d hydrogen in a laser field
The purpose of this exercise is
(1) see how time-propagation with an external field is done
(2) monitor the restricted norm in [-5,5] during time-propagation
(3) see irECS "perfect absorption" at work
[TASK] have a look at input and output,
try to understand how the time-dependence comes into the operator
NOTE: by-pass pulse definition, in the end just the desired vector potential is computed
[TASK] plot the time-evolution of various observables (see file "xxTimeProp/00xx/expec")
interprete what you see
[TASK] Vary the scaling angle theta, what happens?
[TASK] Move the scaling radius all the way to R0=5,
remove the chi[-10,10]:
if complex scaled, it would produce a complex expectation value, which is not allowed
look at the expectationvalues again, which ones are affected?
# laser pulse parameters: cos2 pulse
Laser: shape, I(W/cm2), FWHM, lambda(nm)
cos2, 2.e14, 1. OptCyc, 800.
# time-progation
# from -1 optical cycle (start of the pulse)
# to several optical cycles (long after the field is gone)
# print output at the given intervals
TimePropagation: begin,end,print
-1 OptCyc, 5 OptCyc, 0.1 OptCyc
# NOTE: as a rule, you can specify units for the input
if nothing is specified, usually atomic units are understood
some inputs by default go in units customary in the field
this is noted by the units specified in the definition
# NOTE: the specified units can be overruled by explicitly specifying the
# units after the number, for example
#
# Laser: I(W/cm2)
# 0.01 au
# will result in the equivalent of ~3.51e14W/cm2
#
# internally, the code uses atomic units (to which all numbers will be converted upon input)
Absorption: kind, axis, theta, upper
ECS,X,0.5,20.
# piece-wise specification of discretization with exponential tails at both ends
Axis: name,nCoefficients,lower end, upper end,functions,order
X,20,-Infty,-20,polExp[1.]
X,80,-20, 20,polynomial,10
X,20, 20, Infty,polExp[1.]
Operator: hamiltonian='0.5-<1/sqrt(Q*Q+2)>'
# interation with the 0 component of a laser field in velocity gauge
# the time-dependent factor is the vector potential A_x(t)
Operator: interaction='iLaserAz[t]<1_d>'
# monitor and also write to file
# the expectation value of the characteristic function in [-5,5] and [-10,10]
Operator: expectationValue=','