ndparamp.xmds

XMDS is a code generator that integrates equations. You write them down in human readable form in a

<?xml version="1.0"?>
<!--Non-Degenerate Parametric Amplifier-->
<!--Simulton formation for logical switching-->

<!-- $Id: ndparamp.xmds,v 1.11 2004/07/14 06:37:05 joehope Exp $ -->

<!--  Copyright (C) 2000-2004                                           -->
<!--                                                                    -->
<!--  Code contributed by Greg Collecutt, Joseph Hope and Paul Cochrane -->
<!--                                                                    -->
<!--  This file is part of xmds.                                        -->
<!--                                                                    -->
<!--  This program is free software; you can redistribute it and/or     -->
<!--  modify it under the terms of the GNU General Public License       -->
<!--  as published by the Free Software Foundation; either version 2    -->
<!--  of the License, or (at your option) any later version.            -->
<!--                                                                    -->
<!--  This program is distributed in the hope that it will be useful,   -->
<!--  but WITHOUT ANY WARRANTY; without even the implied warranty of    -->
<!--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the     -->
<!--  GNU General Public License for more details.                      -->
<!--                                                                    -->
<!--  You should have received a copy of the GNU General Public License -->
<!--  along with this program; if not, write to the Free Software       -->
<!--  Foundation, Inc., 59 Temple Place - Suite 330, Boston,            -->
<!--  MA  02111-1307, USA.                                              -->

<simulation>

  <!-- Global system parameters and functionality -->
  <name>ndparamp</name>

  <author>Unknown Author</author>
  <description>
    Non-degenerate parametric amplifier.  Simulton formation for
    logical switching.
  </description>

  <prop_dim>z</prop_dim>
  <error_check>yes</error_check>
  <benchmark>yes</benchmark>

  <!-- Global variables for the simulation -->
  <globals>
  <![CDATA[
    const double e1 =350;
    const double e2 =350;
    const double r1 = 1;
    const double r2 = 1;
    const double vy1 =  0.5;
    const double vy2 = -0.5;
    const double yc1 = -0.2;
    const double yc2 =  0.2;
    const double tc1 = 0;
    const double tc2 = 0;
    
    double amp1=sqrt(e1/2/M_PI/r1/r1);
    double amp2=sqrt(e2/2/M_PI/r2/r2);
  ]]>
  </globals>

  <!-- Field to be integrated over -->
  <field>
    <name>main</name>
    <dimensions>   y       t     </dimensions>
    <lattice>     50     50    </lattice>
    <domains>  (-10,10) (-10,10) </domains>
    <samples>1 1</samples>

    <vector>
      <name>main</name>
      <type>complex</type>
      <components>ff1 ff2 sh</components>
      <fourier_space>no no</fourier_space>
      <![CDATA[
        ff1 = pcomplex(amp1*exp(-pow((y - yc1)/r1/2,2)
	                        -pow((t - tc1)/r1/2,2)),+vy1*y);
	ff2 = pcomplex(amp2*exp(-pow((y - yc2)/r2/2,2)
	                        -pow((t - tc2)/r2/2,2)),+vy2*y);
	sh  = rcomplex(0,0);
      ]]>
    </vector>

    <vector>
      <name>vc1</name>
      <type>double</type>
      <components>damping</components>
      <fourier_space>no no</fourier_space>
      <![CDATA[
        damping=1.0*(1-exp(-pow((y*y + t*t)/8/8,10)));
      ]]>
    </vector>
  </field>

  <!-- The sequence of integrations to perform -->
  <sequence>
    <integrate>
      <algorithm>RK4IP</algorithm>
      <interval>10</interval>
      <lattice>500</lattice>
      <samples>50 50</samples>
      <k_operators>
        <constant>yes</constant>
        <operator_names>Lap1 Lap2</operator_names>
	<![CDATA[
	  Lap1 = i*(-(ky*ky + kt*kt)   - 1);
	  Lap2 = i*(-(ky*ky + kt*kt)/2 - 1);
	]]>
      </k_operators>
      <vectors>main vc1</vectors>
      <![CDATA[
        dff1_dz = Lap1[ff1] + i*~ff2*sh  - damping*ff1;
	dff2_dz = Lap1[ff2] + i*~ff1*sh  - damping*ff2;
	dsh_dz  = Lap2[sh]  + i* ff1*ff2 - damping* sh;
      ]]>
    </integrate>
  </sequence>

  <!-- The output to generate -->
  <output format="ascii" precision="double">
    <group>
      <sampling>
        <fourier_space> no  no </fourier_space>
        <lattice>       50  0  </lattice>
        <moments>pow_dens</moments>
	<![CDATA[
	  pow_dens = ~ff1*ff1 + ~ff2*ff2 + 2*~sh*sh;
	]]>
      </sampling>
    </group>

    <group>
      <sampling>
        <fourier_space> no  no </fourier_space>
        <lattice>       0  0  </lattice>
        <moments>etot</moments>
	<![CDATA[
	  etot = ~ff1*ff1 + ~ff2*ff2 + 2*~sh*sh;
	]]>
      </sampling>
    </group>
  </output>

</simulation>