Added "n Gaussian" pulse shape

Added support for a sequence of pulses of arbitrary polarization ("n
Gaussian").  An example of usage is in examples/heliumish_raman_circ.inp.

Author: Serguei Patchkovskii

doc/CHANGES.txt

@@ -1,9 +1,14 @@
-Last updated: 2024 February 12
+Last updated: 2026 January 26
 ------------
 
 Change log
 ----------
 
+2026 Jan 26
+
+ - Added field input defined by a sequence of arbitrarily-polarized Gaussian
+   pulses ("n Gaussian").
+
 2024 Feb 12
 
  - Added support for ensemble calculations, where multiple initial

doc/INPUT.txt

@@ -1,4 +1,4 @@
-Last updated: 2024 February 12
+Last updated: 2026 January 26
 ------------
 
   All input to scid-tdse is provided through the sph_tdse namelist, with one
@@ -1047,6 +1047,12 @@ Input keywords
                       Vector-potential along lab Z from VP_SCALE/VP_PARAM
                       Vector-potential along lab X from VP_SCALE_X/VP_PARAM_X
       'xy Gaussian' - Similar to 'zy Gaussian', but in the XY plane
+      'n Gaussian'  - General sequence of Gaussian pulses of arbitrary 
+                      polarization, defined by VP_SCALE_N and VP_PARAM_N.
+                      Sequences of circularly-polarized pulses can be
+                      symthesized using a pair of orthogonal linearly-polarized
+                      pulses with a pi/2 CEP phase shift. All "Gaussian" pulse
+                      sequences above can be synthesized using this form.
       'zx CW'       - Circularly polarized CW field in the ZX plane.
                       VP_SCALE gives the magnitude, VP_PARAM(1) is the
                       (circular) frequency
@@ -1101,6 +1107,16 @@ Input keywords
                      origin [atomic units]
       VP_PARAM(12) - End of the envelope hard turn-off, relative to the 
                      origin [atomic units]. VP_PARAM(12)>VP_PARAM(11).
+    "n Gaussian" pulses above use the same parameters, supplied in the
+    VP_SCALE_N(I) and VP_PARAM_N(:,I) arrays. Additionally, the laboratory-
+    frame Cartesian polarization direction of each pulse should be specified
+    in VP_PARAM(13:15,I). The direction does not need to be normalized; if
+    not specified (or specified as three zeros), Z polarization will be used.
+    If all pulses are Z-polarized, setting ROTATION_MODE='none' is strongly
+    recomended.
+      VP_PARAM(1:4,I)
+      VP_PARAM(11:12,I) - As in "Gaussian" above
+      VP_PARAM(13:15,I) - Cartesian polarization direction
     "Sin2" pulses depend on the following parameters:
       VP_SCALE     - overall vector potential magnitude
       VP_PARAM(1)  - Carrier circular frequency [atomic units]

examples/heliumish_raman_circ.chk

@@ -0,0 +1 @@
+scripts/check_general.sh

examples/heliumish_raman_circ.inp

@@ -0,0 +1,45 @@
+ &sph_tdse
+   comment                = "Alternative Helium potential, Raman excitation via continuum with circular polarization"
+   verbose                = 1,
+   omp_num_threads        = 0,
+   initial_wfn            = 'single',
+   initial_wfn_index      = 0, 0, 1,
+   initial_wfn_energy     = (-0.900,0.0)
+   sd_nradial             = 900,
+   sd_lmax                =   5,
+   sd_mmin                =  -5,
+   sd_mmax                =  +5,
+   sd_rgrid               = 'uniform',
+   sd_rgrid_dr            = 0.10,
+   sd_rgrid_report        = ' '
+   pot_name               = 'input',
+   pot_input(0:12,0)      = 1.0, -1.0, -0.6731, 4.0000,
+                                 -1.0, -0.3269, 0.4000,
+                                  1.0,  0.1056, 0.6618
+   sd_rgrid_zeta          = 2.0,
+   task                   = 'real time',
+   dt                     = 0.02
+   dt_subdivision         = 'off'
+   timesteps              = 127150
+   vp_shape               = 'n Gaussian'
+   field_unwrap           = .true.
+   rotation_mode          = 'auto',
+   vp_scale_n(1)          = 0.03262079
+   vp_scale_n(2)          = 0.03262079
+   vp_param_n(1:4,1)      = 2.07821094, 0.00000000000000000000, 1240.2412, 413.4137
+   vp_param_n(11:15,1)    = 826.8275, 1240.2412,   1.0, 0.0, 0.0
+   vp_param_n(1:4,2)      = 2.07821094, 1.57079632679489661924, 1240.2412, 413.4137
+   vp_param_n(11:15,2)    = 826.8275, 1240.2412,   0.0, 1.0, 0.0
+   vp_scale_n(5)          = 0.04052557
+   vp_scale_n(6)          = 0.04052557
+   vp_param_n(1:4,5)      = 1.32249787, 0.00000000000000000000, 1302.7411, 413.4137
+   vp_param_n(11:15,5)    = 826.8275, 1240.2412,   1.0, 0.0, 0.0
+   vp_param_n(1:4,6)      = 1.32249787, 1.57079632679489661924, 1302.7411, 413.4137
+   vp_param_n(11:15,6)    = 826.8275, 1240.2412,   0.0, 1.0, 0.0
+   skip_tests             = .T.
+   output_each            = 100,
+   composition_threshold  = 1e-6, ! -1 to disable
+   field_preview          = ' ', ! 'heliumish_raman_circ_field.table'
+   wt_atomic_cache_prefix = ' ',
+   detail_output          = ' ',
+ /