1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How to simulate a potential barrier?

  1. Apr 25, 2008 #1
    Hi,

    I am doing simulations on a particle in some potential together with a fluctuating force and friction. To do that, I use the Langevin equation with the fluctuating force being a random number from a normal distribution with a temperature-dependent variance. I use a Verlet-algorithm for the calculation of position, velocity and acceleration (x,v and a) at each timestep.

    My problem is how I can implement a high potential barrier - basically a wall. What I tried so far was to change the sign of x and v once it happens that x<0 (I have the barrier at x=0, and a linear potential at x>0).

    But this gives unrealistic results, the particle goes way to far away from the barrier at very low temperatures - it looks like the particle in some way gets quite much energy when it hits the wall.

    Does anyone have some suggestion on how to implement such a barrier? Or help me explain why my current method fails?

    I can mention it probably isn't problems with the Verlet-algorithm itself or something else, since it yields very nice results if I use a harmonic potential.

    Let me know if you need more information :)
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted