"Delta potential scattering"의 두 판 사이의 차이

수학노트
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<h5>introduction</h5>
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==introduction==
  
*  Let the potential is given by <math>V(x) = \lambda\delta(x)</math><br><math>\psi(x) = \begin{cases} \psi_{\mathrm L}(x) = A_{\mathrm r}e^{ikx} + A_{\mathrm l}e^{-ikx}, & \text{ if } x<0; \\ \psi_{\mathrm R}(x) = B_{\mathrm r}e^{ikx} + B_{\mathrm l}e^{-ikx}, & \text{ if } x>0, \end{cases}</math><br>
+
*  Let the potential is given by  
*  we impose two conditions on the wave function<br>
+
:<math>V(x) = \lambda\delta(x)</math>
**  the wave function be continuous in the origin
+
* wave function
**  integrate the Schrödinger equation around x = 0, over an interval [−ε, +ε] and In the limit as ε → 0, the right-hand side of this equation vanishes; the left-hand side becomes
+
:<math>\psi(x) = \begin{cases} \psi_{\mathrm L}(x) = A_{\mathrm r}e^{ikx} + A_{\mathrm l}e^{-ikx}, & \text{ if } x<0; \\ \psi_{\mathrm R}(x) = B_{\mathrm r}e^{ikx} + B_{\mathrm l}e^{-ikx}, & \text{ if } x>0, \end{cases}</math>
*  first condition<br><math>\psi(0) =\psi_L(0) = \psi_R(0) = A_r + A_l = B_r + B_l</math><br><math>A_r + A_l - B_r - B_l = 0</math><br>
+
*  we impose two conditions on the wave function
*  second condition<br><math> -\frac{\hbar^2}{2 m} \int_{-\epsilon}^{+\epsilon} \psi''(x) \,dx + \int_{-\epsilon}^{+\epsilon} V(x)\psi(x) \,dx = E \int_{-\epsilon}^{+\epsilon} \psi(x) \,dx</math><br> LHS becomes <math>-\frac{\hbar^2}{2m}[\psi_R'(0)-\psi_L'(0)] +\lambda\psi(0)</math><br> RHS becomes 0<br><math>-A_r + A_l + B_r - B_l =\frac{2m\lambda}{ik\hbar^2}(A_r + A_l)</math><br>
+
** the wave function be continuous in the origin
*  the coefficient must satisfy<br><math>A_r + A_l - B_r - B_l = 0</math><br><math>-A_r + A_l + B_r - B_l =\frac{2m\lambda}{ik\hbar^2}(A_r + A_l)</math><br>
+
** integrate the Schrödinger equation around x = 0, over an interval [−ε, +ε] and In the limit as ε → 0, the right-hand side of this equation vanishes; the left-hand side becomes
 +
*  first condition
 +
:<math>\psi(0) =\psi_L(0) = \psi_R(0) = A_r + A_l = B_r + B_l</math>
 +
:<math>A_r + A_l - B_r - B_l = 0</math>
 +
*  second condition
 +
:<math> -\frac{\hbar^2}{2 m} \int_{-\epsilon}^{+\epsilon} \psi''(x) \,dx + \int_{-\epsilon}^{+\epsilon} V(x)\psi(x) \,dx = E \int_{-\epsilon}^{+\epsilon} \psi(x) \,dx</math>
 +
* LHS becomes <math>-\frac{\hbar^2}{2m}[\psi_R'(0)-\psi_L'(0)] +\lambda\psi(0)</math>
 +
* RHS becomes 0
 +
:<math>-A_r + A_l + B_r - B_l =\frac{2m\lambda}{ik\hbar^2}(A_r + A_l)</math>
 +
*  the coefficients <math>A_r, A_l,B_r,B_l</math> must satisfy
 +
:<math>
 +
\begin{cases}
 +
A_r + A_l - B_r - B_l = 0 \\
 +
-A_r + A_l + B_r - B_l =\frac{2m\lambda}{ik\hbar^2}(A_r + A_l)
 +
\end{cases}
 +
</math>
  
 
+
==delta potential scattering==
 
 
 
 
 
 
<h5>delta potential scattering</h5>
 
  
 
* special case of scattering problem <math>A_r=1,  A_l=r,  B_r=t , B_l = 0</math>
 
* special case of scattering problem <math>A_r=1,  A_l=r,  B_r=t , B_l = 0</math>
*  wave function<br><math>\psi(x) = \begin{cases} \psi_{\mathrm L}(x) = e^{ikx} + re^{-ikx}, & \text{ if } x<0; \\ \psi_{\mathrm R}(x) =te^{ikx} , & \text{ if } x>0, \end{cases}</math><br>
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*  wave function
 
+
:<math>\psi(x) = \begin{cases} \psi_{\mathrm L}(x) = e^{ikx} + re^{-ikx}, & \text{ if } x<0; \\ \psi_{\mathrm R}(x) =te^{ikx} , & \text{ if } x>0, \end{cases}</math>
 
 
 
 
* <math>t-r=1</math><br><math>t=\cfrac{1}{1-\cfrac{m\lambda}{i\hbar^2k}}\,\!</math><br><math>r=\cfrac{1}{\cfrac{i\hbar^2 k}{m\lambda} - 1}\,\!</math><br><math>R=|r|^2=\cfrac{1}{1+\cfrac{\hbar^4k^2}{m^2\lambda^2}}= \cfrac{1}{1+\cfrac{2\hbar^2 E}{m\lambda^2}}.\,\!</math><br><math>T=|t|^2=1-R=\cfrac{1}{1+\cfrac{m^2\lambda^2}{\hbar^4k^2}}= \cfrac{1}{1+\cfrac{m \lambda^2}{2\hbar^2 E}}\,\!</math><br>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
<h5>history</h5>
 
 
 
* http://www.google.com/search?hl=en&tbs=tl:1&q=
 
 
 
 
 
  
 
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* <math>t-r=1</math>
 +
:<math>t=\cfrac{1}{1-\cfrac{m\lambda}{i\hbar^2k}}\,\!</math>
 +
:<math>r=\cfrac{1}{\cfrac{i\hbar^2 k}{m\lambda} - 1}\,\!</math>
 +
:<math>R=|r|^2=\cfrac{1}{1+\cfrac{\hbar^4k^2}{m^2\lambda^2}}= \cfrac{1}{1+\cfrac{2\hbar^2 E}{m\lambda^2}}.\,\!</math>
 +
:<math>T=|t|^2=1-R=\cfrac{1}{1+\cfrac{m^2\lambda^2}{\hbar^4k^2}}= \cfrac{1}{1+\cfrac{m \lambda^2}{2\hbar^2 E}}\,\!</math>
  
<h5>related items</h5>
+
  
 
+
==계산 리소스==
 +
* https://docs.google.com/file/d/0B8XXo8Tve1cxZjdDY3BfRFEwM0E/edit
  
 
+
  
<h5 style="line-height: 3.428em; margin: 0px; color: rgb(34, 61, 103); font-family: 'malgun gothic',dotum,gulim,sans-serif; font-size: 1.166em; background-position: 0px 100%;">encyclopedia</h5>
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==encyclopedia==
  
 
* [http://en.wikipedia.org/wiki/Delta_potential_barrier_%28QM%29 http://en.wikipedia.org/wiki/Delta_potential_barrier_(QM)]
 
* [http://en.wikipedia.org/wiki/Delta_potential_barrier_%28QM%29 http://en.wikipedia.org/wiki/Delta_potential_barrier_(QM)]
* http://www.scholarpedia.org/
+
[[분류:physics]]
* [http://eom.springer.de/ http://eom.springer.de]
+
[[분류:math and physics]]
* http://www.proofwiki.org/wiki/
+
[[분류:migrate]]
* Princeton companion to mathematics([[2910610/attachments/2250873|Companion_to_Mathematics.pdf]])
 
 
 
 
 
 
 
 
 
 
 
<h5>books</h5>
 
 
 
 
 
 
 
* [[2011년 books and articles]]
 
* http://library.nu/search?q=
 
* http://library.nu/search?q=
 
 
 
 
 
 
 
 
 
 
 
<h5>expositions</h5>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
<h5 style="line-height: 3.428em; margin: 0px; color: rgb(34, 61, 103); font-family: 'malgun gothic',dotum,gulim,sans-serif; font-size: 1.166em; background-position: 0px 100%;">articles</h5>
 
 
 
 
 
 
 
* http://www.ams.org/mathscinet
 
* http://www.zentralblatt-math.org/zmath/en/
 
* http://arxiv.org/
 
* http://www.pdf-search.org/
 
* http://pythagoras0.springnote.com/
 
* [http://math.berkeley.edu/%7Ereb/papers/index.html http://math.berkeley.edu/~reb/papers/index.html]
 
* http://dx.doi.org/
 
 
 
 
 
 
 
 
 
 
 
<h5>question and answers(Math Overflow)</h5>
 
 
 
* http://mathoverflow.net/search?q=
 
* http://mathoverflow.net/search?q=
 
 
 
 
 
 
 
 
 
 
 
<h5>blogs</h5>
 
 
 
*  구글 블로그 검색<br>
 
**  http://blogsearch.google.com/blogsearch?q=<br>
 
** http://blogsearch.google.com/blogsearch?q=
 
* http://ncatlab.org/nlab/show/HomePage
 
 
 
 
 
 
 
 
 
 
 
<h5>experts on the field</h5>
 
 
 
* http://arxiv.org/
 
 
 
 
 
 
 
 
 
 
 
<h5>links</h5>
 
  
* [http://detexify.kirelabs.org/classify.html Detexify2 - LaTeX symbol classifier]
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==메타데이터==
* [http://pythagoras0.springnote.com/pages/1947378 수식표현 안내]
+
===위키데이터===
* [http://www.research.att.com/%7Enjas/sequences/index.html The On-Line Encyclopedia of Integer Sequences]
+
* ID :  [https://www.wikidata.org/wiki/Q2381860 Q2381860]
* http://functions.wolfram.com/
+
===Spacy 패턴 목록===
 +
* [{'LOWER': 'delta'}, {'LEMMA': 'potential'}]

2021년 2월 17일 (수) 02:30 기준 최신판

introduction

  • Let the potential is given by

\[V(x) = \lambda\delta(x)\]

  • wave function

\[\psi(x) = \begin{cases} \psi_{\mathrm L}(x) = A_{\mathrm r}e^{ikx} + A_{\mathrm l}e^{-ikx}, & \text{ if } x<0; \\ \psi_{\mathrm R}(x) = B_{\mathrm r}e^{ikx} + B_{\mathrm l}e^{-ikx}, & \text{ if } x>0, \end{cases}\]

  • we impose two conditions on the wave function
    • the wave function be continuous in the origin
    • integrate the Schrödinger equation around x = 0, over an interval [−ε, +ε] and In the limit as ε → 0, the right-hand side of this equation vanishes; the left-hand side becomes
  • first condition

\[\psi(0) =\psi_L(0) = \psi_R(0) = A_r + A_l = B_r + B_l\] \[A_r + A_l - B_r - B_l = 0\]

  • second condition

\[ -\frac{\hbar^2}{2 m} \int_{-\epsilon}^{+\epsilon} \psi''(x) \,dx + \int_{-\epsilon}^{+\epsilon} V(x)\psi(x) \,dx = E \int_{-\epsilon}^{+\epsilon} \psi(x) \,dx\]

  • LHS becomes \(-\frac{\hbar^2}{2m}[\psi_R'(0)-\psi_L'(0)] +\lambda\psi(0)\)
  • RHS becomes 0

\[-A_r + A_l + B_r - B_l =\frac{2m\lambda}{ik\hbar^2}(A_r + A_l)\]

  • the coefficients \(A_r, A_l,B_r,B_l\) must satisfy

\[ \begin{cases} A_r + A_l - B_r - B_l = 0 \\ -A_r + A_l + B_r - B_l =\frac{2m\lambda}{ik\hbar^2}(A_r + A_l) \end{cases} \]

delta potential scattering

  • special case of scattering problem \(A_r=1, A_l=r, B_r=t , B_l = 0\)
  • wave function

\[\psi(x) = \begin{cases} \psi_{\mathrm L}(x) = e^{ikx} + re^{-ikx}, & \text{ if } x<0; \\ \psi_{\mathrm R}(x) =te^{ikx} , & \text{ if } x>0, \end{cases}\]

  • \(t-r=1\)

\[t=\cfrac{1}{1-\cfrac{m\lambda}{i\hbar^2k}}\,\!\] \[r=\cfrac{1}{\cfrac{i\hbar^2 k}{m\lambda} - 1}\,\!\] \[R=|r|^2=\cfrac{1}{1+\cfrac{\hbar^4k^2}{m^2\lambda^2}}= \cfrac{1}{1+\cfrac{2\hbar^2 E}{m\lambda^2}}.\,\!\] \[T=|t|^2=1-R=\cfrac{1}{1+\cfrac{m^2\lambda^2}{\hbar^4k^2}}= \cfrac{1}{1+\cfrac{m \lambda^2}{2\hbar^2 E}}\,\!\]


계산 리소스


encyclopedia

메타데이터

위키데이터

Spacy 패턴 목록

  • [{'LOWER': 'delta'}, {'LEMMA': 'potential'}]