"Quantum scattering"의 두 판 사이의 차이

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* [[Schrodinger equation]]<br><math>E \psi = -\frac{\hbar^2}{2m}{\partial^2 \psi \over \partial x^2} + V(x)\psi</math><br>
 
* [[Schrodinger equation]]<br><math>E \psi = -\frac{\hbar^2}{2m}{\partial^2 \psi \over \partial x^2} + V(x)\psi</math><br>
*  simplified form<br><math>-\varphi_{xx}+u(x)\varphi = \lambda\varphi</math><br>  <br><math>\varphi_{xx}+(\lambda-u(x))\varphi=0</math><br>
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*  simplified form<br><math>-\varphi_{xx}+u(x)\varphi = \lambda\varphi</math><br><math>\varphi_{xx}+(\lambda-u(x))\varphi=0</math><br>
  
 
 
 
 
43번째 줄: 43번째 줄:
 
<h5>delta potential example</h5>
 
<h5>delta potential example</h5>
  
* [[search?q=delta%20potential%20scattering&parent id=7236371|delta potential scattering]]
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* [[delta potential scattering]]
  
 
 
 
 

2011년 2월 10일 (목) 05:59 판

introduction

 

 

 

time independent Schrodinger equation
  • Schrodinger equation
    \(E \psi = -\frac{\hbar^2}{2m}{\partial^2 \psi \over \partial x^2} + V(x)\psi\)
  • simplified form
    \(-\varphi_{xx}+u(x)\varphi = \lambda\varphi\)
    \(\varphi_{xx}+(\lambda-u(x))\varphi=0\)

 

 

continuous spectrum
  • e^{ikx} represents a wave traveling to the right, and e^{−ikx} one traveling to the left
  • e^{−ikx} is incoming wave from the right to the left
  • reflection and transmission coefficient
    \(\varphi \sim e^{-ikx}+\rho(k,t)e^{ikx}\) as \(x\to +\infty\)
    \(\varphi \sim \tau(k,t)e^{-ikx}\) as \(x\to -\infty\)
    \(\rho(k,t)\) and \(\tau(k,t)\) are called the reflection and transmission coefficient

 

potential scattering

\(r=t-1\)

If t is of the form \(t=\frac{1}{1-ai}\) (real number a), then

\(|r|^2+|t|^2=1\)

 

 

delta potential example

 

 

harmonic oscillator

 

 

example
  1. \[Lambda] := -1
    u[x_] := -2 Sech[x]^2
    f[x_] := Sech[x]
    Simplify[D[D[f[x], x], x] + (\[Lambda] - u[x]) f[x]]
    Plot[u[x], {x, -5, 5}]

 

 

 

history

 

 

related items

 

 

encyclopedia

 

 

books

 

 

 

expositions

 

 

 

articles

 

 

question and answers(Math Overflow)

 

 

blogs

 

 

experts on the field

 

 

links