All Questions
Tagged with coherent-states quantum-spin
10
questions
1
vote
0
answers
33
views
Coherent spin state (CSS) for an electron with spin
Standard definition for the spin coherent state (CSS) for the system of $N$ identical particles reads
$$
|\theta, \phi\rangle = \bigotimes\limits_{k=1}^{N} \left[ \cos\frac{\theta}{2} |0\rangle_k + e^{...
- 227
0
votes
1
answer
332
views
Is $SU(2)$ coherent state normalized?
I know Glauber coherent state are normalized such that the inner product of < α|α > =1 where |α > is Glauber coherent state.
My question is (is SU(2) COHERENT STATE NORMALIZED)?
I MEAN IF |Z&...
- 11
8
votes
4
answers
1k
views
In what sense are spin coherent states "classical"?
Spin coherent states are often introduced as "the most classical states of a finite-dimensional system", or as the analogous of coherent states of light for finite-dimensional systems. See e....
- 14.8k
1
vote
0
answers
75
views
How to calculate spin correlation function via spin coherent state?
I am following the Section 8.3.1 of Auerbach. I want to calculate spin correlation function via spin coherent state, i.e. the equation (8.28):
$$\begin{aligned}\left\langle\mathbf{S}_{m} \cdot \mathbf{...
- 1,602
4
votes
1
answer
541
views
How to calculate the expectation value in spin coherent state?
In Shankar, QFT and Condensed Matter, p73, it says
$$\langle S,S|\vec S|SS\rangle=\vec kS,\tag{6.3}$$
$$\langle\Omega|\vec S|\Omega\rangle=S(\vec i \sin\theta \cos\phi+\vec j \sin\theta \sin\phi+\...
- 483
1
vote
0
answers
25
views
Numerical method to find the roots of the expected value of a spin 2j state
Currently I am working with finding the solutions for the following problem:
I have a unit sphere in which I have n points defined by their polar and azimuthal angles: $\theta_n , \phi_n$. I then do ...
2
votes
3
answers
942
views
Spin coherent state for general spin $S$
In Wen's book on Many-body QFT, he claimed that the coherent state for a spin-$S$ particle can be written as a tensor product of $2S$ spin-1/2 coherent states:
$$|\hat{n}\rangle=|z\rangle\otimes|z\...
- 2,301
0
votes
0
answers
93
views
Can we define the spin coherent state for spin half operator $\vec{S}$?
Here I meet two kinds of definitions for the spin coherent state:
$\vec{\widehat{S}}|\vec{n}\rangle=S\vec{n}|\vec{n}\rangle$ (in my quantum field theory course);
$\vec{n}\cdot\vec{\widehat{S}}|\vec{n}...
- 1,757
0
votes
1
answer
575
views
Time evolution of a spin-coherent state
What i'm struggling with is this question:
Consider a spin S in an external magnetic field along the quantization axis so that the $|S_{z}>$ states are eigenstates with equally spaced eigenvalues ...
1
vote
1
answer
386
views
Quantum mechanical spin coherent states
I'm really struggling with how to derive the right hand side of this equation. It's the Spin operator on coherent states of the harmonic oscillator. I've done it for the $S_+$ operator but can't seem ...