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Author Topic: Do masers and lasers work after the same principle?  (Read 10180 times)

Offline sorincosofret

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Do masers and lasers work after the same principle?

The presented experiment need only an on-off switch and  few neurons to interpret the results.

Background and actual explanation

The theoretical basis upon which both the maser and laser rest was laid by Albert Einstein in 1917 with a paper entitled "On the Quantum Theory of Radiation," which introduced the process of stimulated emission.
To describe the phenomenon of spontaneous emission (fig. 1), let us consider two  energy levels, E1 and E2,  where  E1 is ground level and E2 an excited level, with E1< E2.
If an atom is arrived in excited state (E2), since E2>E1 it will tends spontaneous to decay to the ground state (E1) by ,,spontaneous emission’’.  The corresponding energy difference must therefore be released by the atom. Spontaneous emission is therefore characterized by the emission of a photon of energy hν = E2— E1. 
Einstein predicted that in addition to the spontaneous emission of photons from excited atoms, there is an emission forced by radiation to which the atoms might be exposed.
Let us now suppose that the atom is initially found in excited state (E2) and a photon of frequency ν, equal to that of the spontaneously emitted photon is incident on the material.
In this case, two photons of precisely the same wavelength and direction are produced (fig. 1-b) and this was called stimulated emission.
The overall result for a greater number of excited atoms is a cascade of photons, all traveling in the same direction and with the same frequency and phase as the photons that shake out the excited atoms.



Figure 1. Spontaneous and stimulated emission



Why is the actual explanation erroneous?

A true theory of physics must respond at least 3 fundamental questions about maser and laser and the differences between lasers and masers arise implicit.
These questions are:
1.   Are the maser and laser experimental set up identical with up presented theoretical consideration?
2.   Why it is possible to have a self-sustaining radiation in case of maser and not in case of laser?
3.   Why a laser can’t work with only two levels of energy?

The present text responds in detail only to the first question; the complete answers are in present or further books. 
As was seen at Masers and quantum hypothesis link, there are more possibilities to obtain the population inversion. The present discussion will be focused on the separation of particle from beam due to an inhomogeneous magnetic field; the conclusions are valid for all other population inversion methods too.
Quantum mechanic admit that a inhomogeneous magnetic field with a distribution like in fig. 1 is able to act like a ,,state selector”. The atoms in the upper energy level are entering into the cavity and the atoms in the lower energy level are removed.



Figure 1. Maser principle with different types of state selectors

Some problems are arising from this interpretation:
-   What’s happened if the configuration of the magnetic field is inversed?
-    What physical phenomena represent the basis of population inversion?
-   What kind of energy emits a particle found in the higher energy level, in absence of the background resonant microwave?

If the fact that magnet has a hexapol distribution is omitted, it is possible to make a analogy between the Stern Gerlach experiment and the action of ,,state selector”. If the polarity of magnet is changed, according to actual quantum interpretation, the atoms found in upper energy state are rejected and in cavity enter the atoms in low energy state. In this case, the background microwave can’t act to produce stimulated emission, and it should be registered no signal from maser.
The proposed theory, affirm that independent on the polarity change of  ,,selector state” the same signal will be registered at from maser.
In actual quantum mechanic is not clearly delimitate what phenomena lay at the base of population inversion for maser case. In principle, a magnetic field (homogenous or inhomogeneous) does not produce a  ,,population inversion”. A magnetic field produces only a deviation of a particle.
A magnetic moments (see the atomic book) entering into an inhomogeneous magnetic field will be acted by a force, and the direction of this force depend both on the inhomogeneous magnetic field and orientation of magnetic moment. But this does not mean a ,, population inversion”. Maybe in this case, the process of atoms generation is responsible on this ,,population inversion” ? The actual physics should delimitate clearly this problem.
The reality is simpler. In proposed theory the inhomogeneous magnetic field has a simple purpose to select from a fascicle of atoms a sub fascicle with a specific orientation of their magnetic moments.
   If the quantum theory is correct, in the absence of a background microwave, the fascicle of atoms in the upper level which enter in resonant cavity should decay on the ground level and a spontaneous emission should be counted. Of course, a real quantum theory should provide a distribution with frequency for this radiation. 
   In proposed theory there is no such emission, because an atom entering into cavity is not excited, only its magnetic moment has a specific direction.
   It is very easy to be tested the difference between actual quantum theory and proposed one….
The proposed experiment supposes only a disconnection of microwave background which enters in resonant cavity and to interpret the results….





 

Offline Bored chemist

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Do masers and lasers work after the same principle?
« Reply #1 on: 20/10/2008 20:15:40 »
Do masers and lasers work after the same principle?


Yes.
 

Offline sorincosofret

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Do masers and lasers work after the same principle?
« Reply #2 on: 21/10/2008 06:11:35 »
in this case shut down the background microwave and you will observe the spectrum of the transition between excited state and ground state.
Does it exists and respect the Planck distribution ?
 

Offline Bored chemist

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Do masers and lasers work after the same principle?
« Reply #3 on: 21/10/2008 06:55:14 »
"in this case shut down the background microwave "
How?
 

Offline sorincosofret

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Do masers and lasers work after the same principle?
« Reply #4 on: 21/10/2008 10:45:05 »
At the maser resonant cavity you have two waveguide. One is the background microwave produced  using a electronic or other type (klystron)circuits and there is a second wave guide necessary for the produced microwave as results of the transition between excited state and ground state.
You must find a possibility to block the background microwave or to shut down the current in the circuit of microwave generator.
After that you wait until the excited particles in inhomogeneous magnetic field start to emit microwave.
When you will have obtained spontaneous transition as result of the magnetic deflection of atoms or molecule, I will cut all my posts and you will never hear something about me.
In the meantime as I'm sure that you are not able to find the correct circuit cable to be disconnected give me the scheme of your instrument.
 

Offline Bored chemist

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Do masers and lasers work after the same principle?
« Reply #5 on: 21/10/2008 19:00:12 »
Do you really think anyone here has a hydrogen maser that they ware going to mess up just to prove that you are wrong. Come to that, do you think anyone here has one at all?
 

lyner

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Do masers and lasers work after the same principle?
« Reply #6 on: 21/10/2008 19:27:46 »
Sorin
Do you not realise the essential difference between the ways microwaves can be produced in a coherent way and the ways (without a laser) that optical light can be produced?
The two regions of the em spectrum are significantly different in practical terms so the way you produce stimulated emission must be different for each device. The theory is the same but the details are different.
Rather than shooting from the hip, perhaps you should do some more reading about stuff and you might understand it better before, yet again, you attempt to re-write the whole of Science.
Do you realise that, as soon as you stop ranting on about these things, the 'system' will resume its steady progress and you will sink out of sight. Your promised publications will never emerge.
 

Offline sorincosofret

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Do masers and lasers work after the same principle?
« Reply #7 on: 21/10/2008 21:35:50 »
A saying with a lot of true inside:
Românul îşi cheltuieşte viaţa dovedindu-şi dreptatea. ( A Romanian spend his life only to proof the truth).
This was our destiny as nation and If the history repeats.. I will accept this fact.
But if the conditions will be on my side....

Coming back to the subject. Please tell me what are the differences between a laser in IR and a laser in visible.
IR is close to microwave, so after that please make me a comparative analysis between a maser in microwave and a laser in IR.
You will see alone how big are the differences and I don't' speak about experimental setting or experimental setup. I speak about different working principle.
 

lyner

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Do masers and lasers work after the same principle?
« Reply #8 on: 21/10/2008 22:59:19 »
One of the big divisions in the em spectrum is between the shortest microwaves which can be generated, detected and amplified in coherent terms and IR for which the associated devices can only be detected by non coherent means. The Laser, as a tool, makes life a bit different but the basic practical difference still exists. BUT, when stimulated emission is concerned, the quantum nature of em is an essential part. Masers use the same principle as lasers. Indeed, I have a book by OS Heavens called Optical Masers (an elderly one of course
The duality principle says you can always treat em as a quantum phenomenon but sometimes it's just not the easiest way. BUT Masers are quantum devices, totally. The actual transitions which are involved are different as you move through the spectrum but the theory does not need to distinguish.

Whilst talking of the truth - I think you should examine its meaning in all your assertions. Can you really be right that everyone else is wrong in all these matters?
« Last Edit: 21/10/2008 23:01:52 by sophiecentaur »
 

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Do masers and lasers work after the same principle?
« Reply #8 on: 21/10/2008 22:59:19 »

 

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