• Support PF! Buy your school textbooks, materials and every day products Here!

Help understanding easy state problem

  • Thread starter narfarnst
  • Start date
  • #1
14
0
First off, I don't need a solution, I just need to make sens of the solution I already have.

Homework Statement


What state of polarization do the following represent (Give your answer in terms of an angle relative to the transmission axis).
(a). |t> + |a>
(b) |t> + 2|a>
(c) 2|t>-|a>
-------
My professor has given us the solutions:
(a). arctan(1) = 45 deg.
(b). arctan(2)~65 deg
(c). arctan(-1/2)~27 deg.

From this, I've reverse-engineered that to find the answer in general, for m|t>+n|a> you take arctan(n/m).

But.... what the hell does this mean, and how is it derived?

Thanks.
 

Answers and Replies

  • #2
213
8
't' stands for transverse and 'a' for axial and all that means is that they are the basis vectors of the polarisation vector and their coefficients are the components. Similar to (x,y) and the angle between them is arctan (y/x)
 
  • #3
14
0
Thanks.

But why use bra-ket notation? Couldn't you just as easially express them as (a, t). For example, (2, -1) or (1, 1).
 
  • #4
213
8
yes they're equivalent, but the advantages of bra-ket notation are lost in this examble
 
  • #5
14
0
Ahhh, well thanks again.
 

Related Threads on Help understanding easy state problem

  • Last Post
Replies
7
Views
2K
  • Last Post
Replies
3
Views
4K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
4
Views
1K
Replies
27
Views
2K
Replies
1
Views
2K
Replies
10
Views
786
  • Last Post
Replies
0
Views
2K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
2
Views
858
Top