Recent content by luxiaolei

Dear all, Could anyone please explain to me for a 3 level syste, coupled with 2 lasers, what is the equation describing the disspative term of the equation of motion of the density matrix? I am looking for a non-radiative decay, namely the overall population should conserved. I have found...

Hi,all, I m an undergrades and I am suffering on understanding the different representation transformations, namely from schrodinger picture to interaction picture tupically, my lecturer didn't state which representation he was using and I m so confused, any helps would be great. Shall I bring...

Hi all. I m stucked on the question followed, any helps will be greatly appreciated. A perturbation has the form H'=z act on a two level system which they have different parity. So the first order correction to the energy level 1 and 2 are give by: E11=<ψ1| H' |ψ1> Same for level 2...

Thank you so much!

Hi all, I must misunderstood somewhere, couldn't figure out the following, any helps will be greatly appreciated. The first order correction of the pertubated energy is: \leftψn0\langle H'\rightψn0\rangle Where: ψn0 Is the solution of the unpertubated Hamiltonian. My question is can ψn0 be...

Thank you very much indeed, now I am happy now. Great answer.

thank you very much indeed, and your answer is absolutely fantastic! I am very appreciated it, people like you make the forum a great place!

Dear all: I knew the coherent state is the eigenstate of annihilation operator with a complex eigenvalue, which seriously disturbed me of thinking it. Can anyone give me a simple and understandable picture of what is it, thanks a lot in advance.

hi all, can anyone help me understanding what is the meaning of the mixing state of 2p and 2s? thanks in advance. when an electron in n=2 sate in a hydrogen atom, experience a external em field, then the degenerate states split into 3 classes, which are: 1/sqrt2( 210 + 200 ) with higher...

Homework Statement what is the possible wave functions of a two hydrogen atom system under a pertubation, if one of them was perpared in 2s0 and the other was perpared in 2p0 state.Homework Equations The Attempt at a Solution I have no idea of the total wave function should be the sum of both...

hi all. i am trying to calculate the interaction between two excited hydrogen atoms, using degenerate perturbation theory. but comes up a few problems, any helps will be greatly appreciated. the perturbation has the form: H`=e3/R3(XaXb+YaYb-2ZaZb) where the R is the distancee between two...

@DiracRules Thank you for your replay, and it's indeed a great help. Now I am just waiting for more people to come and bring more ideas:) thanks again.

Hi all, I am sure this is a quite simple question but I just can't figure it out, any helps would be greatly appreciated. If a particle stay in a state in a very short time, then by energy time uncertainty relation, it's energy must has a great uncertainty. Also because of energy is propotion...

I have came up some question asking the velocity change of the rocket in its instantaneous rest frame. And I have been taught that in the instantaneous rest frame, v=0, dgamma/dt =0, gamma = 1. if v is always zero, how come to talk about the change in velocity? Thanks in advance

Thanks alxm, great answer, I am now understood. Thank you