radsym.xmds

<?xml version="1.0"?>
<!-- Simulates propagation of 3D atom-molecular BEC on a 1D lattice assuming radial symmetry. -->

<simulation>

  <name>radsym</name>
  
  <author>Tim Vaughan</author>
  <description>
    Simulates propagation of 3D atom-molecular BEC on a 1D lattice assuming radial symmetry.
  </description>

  <prop_dim>t</prop_dim>
  <error_check>yes</error_check>
  <stochastic>no</stochastic>
  <argv>
    <arg>
      <name>alpha_11</name>
      <type>double</type>
      <default_value>0.01</default_value>
    </arg>
    <arg>
      <name>gam</name>
      <type>double</type>
      <default_value>0.01</default_value>
    </arg>
  </argv>

  <globals>
  <![CDATA[  
    const double A = 31.9404;
    const double B = 32.2065;
    const double a = 1.8605;
    const double b = 2.2386;

    const double AG = 10;
    const double PG = 50;
    const double R = 15;
    const double T = 14;

    const double epsilon=0.0;
  ]]>
  </globals>

  <field>
    <name>main</name>
    <dimensions>r</dimensions>
    <lattice>201</lattice>
    <domains>(-1,1)</domains>
    <samples>1 1</samples>
    <vector>
      <name>main</name>
      <type>complex</type>
      <components>ur vr</components>
      <fourier_space>no</fourier_space>
      <![CDATA[
        //ur = complex(r*A*exp(-r*r*R*R*a),0);
        //vr = complex(r*B*exp(-r*r*R*R*b),0);
        ur = complex(r*A*exp(-sqrt(r*r*R*R*a*a + epsilon)),0);
        vr = complex(r*B*exp(-sqrt(r*r*R*R*b*b + epsilon)),0);
      ]]>
    </vector>
    <vector>
      <name>vc1</name>
      <type>double</type>
      <components>damp</components>
      <fourier_space>no</fourier_space>
      <![CDATA[
        damp = AG*pow(sin(r*0.5*M_PI),PG);
      ]]>
    </vector>
  </field>

  <sequence>
    <integrate>
      <algorithm>RK4EX</algorithm>
      <interval>1</interval>
      <lattice>100000</lattice>
      <samples>200 200</samples>
      <k_operators>
        <constant>yes</constant>
        <operator_names>L1 L2</operator_names>
        <![CDATA[
          L1 = -i*T/R/R*(kr*kr);
          L2 = -0.5*i*T/R/R*(kr*kr);
        ]]>
      </k_operators>
      <iterations>3</iterations>
      <vectors>main vc1</vectors>
      <![CDATA[
        complex u = ur/r;
        complex v = vr/r;

        dur_dt = L1[ur] - i*r*T*(u - conj(u)*v + alpha_11*conj(u)*u*u - i*damp*u);
        dvr_dt = L2[vr] - 0.5*i*r*T*(gam*v - u*u - i*damp*v);
      ]]>
    </integrate>
  </sequence>

  <output>
    <group>
      <sampling>
        <fourier_space>no</fourier_space>
        <lattice>201</lattice>
        <moments>Iu Iv</moments>
        <![CDATA[
          Iu = mod2(ur/r);
          Iv = mod2(vr/r);
        ]]>
      </sampling>
    </group>
    <group>
      <sampling>
        <fourier_space>no</fourier_space>
        <lattice>0</lattice>
        <moments>Na Nm Ntot Rout Tout</moments>
        <![CDATA[
          Na = 2*M_PI*R*R*R*mod2(ur);
          Nm = 2*M_PI*R*R*R*mod2(vr);
          Ntot = Na + 2*Nm;
          Rout = R/2.0;
          Tout = T/2.0;
        ]]>
      </sampling>
    </group>
  </output>
</simulation>