One Photon from coil and battery

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    Battery Coil Photon
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Discussion Overview

The discussion centers around the feasibility of generating a single photon using a coil and battery setup. Participants explore various methods and the underlying physics, including energy transitions and the application of E = hf in this context.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant inquires about methods to generate a single photon, suggesting approaches like slowly increasing voltage or using a step voltage.
  • Some participants assert that it is not possible to create single photons through the proposed classical setup, emphasizing that single-photon sources require energy transitions.
  • Another participant expresses confusion about the physics involved, questioning whether a coil can release a single photon and considering the use of filtering methods.
  • A participant explains the energy calculations involved, noting that the energy required to produce a single photon is extremely low, but practical limitations exist due to thermal radiation and the current needed.
  • There is mention of the possibility of generating single photons using sophisticated equipment, such as high-quality microwave resonators at low temperatures.
  • Participants discuss the challenges of detecting a single photon, particularly at low frequencies, while noting that detectors are available for higher frequencies.
  • One participant seeks information on where to obtain single photon detectors for private use, particularly those compatible with a red laser.

Areas of Agreement / Disagreement

Participants generally agree that generating a single photon using the described classical methods is not feasible. However, there are competing views regarding the specifics of photon generation and detection, and the discussion remains unresolved on practical implementations.

Contextual Notes

Limitations include the dependence on specific setups for photon generation, the impact of thermal radiation, and the unresolved nature of the calculations presented by participants.

Who May Find This Useful

This discussion may be of interest to individuals exploring photon generation techniques, those studying quantum optics, or anyone interested in the practical aspects of single photon detection.

wawens
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I need only one photon from a coil and battery set up.


Anyone know how I can get just one photon?
e.g. 1) slowly increasing ramp voltage that spits out single photons slowly?
2) Send a tiny voltage in by pushing a switch?
3) Have many windings or just a few?

Any clues please, would be most grateful. How does E = hf apply to a coil exactly?
http://www.ronsit.co.uk/weird_at_Heart.asp

wawens
 

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You cannot create "single photons" this way. All single-photon sources are created via energy transition, not 'classical' setup like this.Zz.
 
I need just one photon

But a coil would release photons, so cannot I get just one?
Say, I make a 'step' by applying a step voltage to a coil? or
filter the stream somehow (but how?)

I must have some basic misunderstanding of school physics if
only atom energy transitions allow me to get a single photon.
 
There are no physics in which to apply to the technique that you are describing that can get you one photon at a time.

Zz.
 
It is indeed impossible to generatore single photons this way. There are many reasons why; but one "obvious" problem should be the energies involved. Try calculating the energy of a photon (in a setup like this the relevant frequency is probably a few hundred kHz at most) then compare that number to the energy in the coil.
Even if you could generate a number state (i.e. a state with a definite number of photons, e.g. 1) you would end up with an enormous amount of photons, not one.
As an excersise you can also try calculating the number of photons generated in the same frequency range due to the thermal radiation (because the coil is at room temperature and not at zero kelvin).

I should perhaps point out that it IS possible to generate single photons using electrical circuits, i.e. high-quality microwave resonators operated at very low temperatures, but you need some pretty sophisticated equipment.
 
Yes, thanks f95toli, I calculated that even for a very low inductance coil the current needed to produce one photon is thousandths of a microamp. My yellow plastic voltmeter does not go that low and, as you righlty say, thermal photons would be everywhere messing my experiments up - the little wrigglers!

Appendix:
Here's my calculation (its only a rough measure of current needed to produce
one phorton in a very small coil at 100 KHz)

e = hf joules (for one photon_
= 100*1000*6.63*exp-34 joules
= 6.63*exp-29 joules
= LI2/2 -for a small air coil at VHF
i = root (2*6.63*exp-29/L)
3 turns of lentgh 10 mm and radius 5 mm = 0.018443 µH
i = root(2*6.63*exp-29/.02*exp-6)
= root(6.63exp-21)
= 8exp-11 amps wow, thtas small
 
even if you can produce a single photon (in , how could you detect that photon? to improve that if it is true or not
 
miftah said:
even if you can produce a single photon (in , how could you detect that photon? to improve that if it is true or not

In this case it would be difficult (probably impossible) since the frequency is so low. However, once you reach a a frequency of a few terahertz (far infrared) good single photon detectors are readily available.
There are also detectors that can operate down to a few tens of GHz (something like 90 GHz) and at least in principle detect a single photon.
 
Single Photon Detector

You mentioned single photon detectors are readily available.
I am not in a School/University scene at present, so where can I get
them privately? I suppose one that would go with a red laser?
 

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