Photon -phonon interaction ?

[kos]

So sounds crazy but disregarding the different nature of thoose 2 kinds of waves , what would happen when they are propagating in the same medium. From quantum mechanical prespective for instance do the two wavefunctions interact each other someway. What would be the result . Or let me simplify my question . What is going to be if you talk to an antenna since it carries some EM radio waves and you add it your acoustic vibrations ?

[Klaynos]

What you want to look at is phonon polaritons. You can couple the two together.

[kos]

How will additional vibration of sound affect the electromagnetic wave emited from the antenna ?

[Klaynos]

How will additional vibration of sound affect the electromagnetic wave emited from the antenna ?

If they're not coupled the effect will probably be indistinguishable.

[kos]

and what If they are . What does it mean . Would the signal emitted from the antenna differ from the original that should be if there was no applies in sense of vibration.

[swansont]

In an acousto-optic modulator you add RF to a crystal, and have light bounce off of the vibrating lattice, which is probably described by a photon-phonon interaction (I just use them. I never bothered with the nuts and bolts of the theory). The frequency of light increases or decreases by a multiple of the frequency of the added RF, and steers accordingly as the vibrations are transverse to the light.

 

https://en.wikipedia.org/wiki/Acousto-optic_modulator

"The interaction can be thought of as a three-wave mixing process resulting in Sum-frequency generation or Difference-frequency generation between phonons and photons."

[kos]

So on theory If I go close to an antenna take a loadspeaker and start screaming I will change the original RF signal that the antenna would emit

[Carrock]

So on theory If I go close to an antenna take a loadspeaker and start screaming I will change the original RF signal that the antenna would emit

Some of the early A.M. transmitters used carbon microphones (as used in telephones) to modulate the carrier so it's not just theory!

[Enthalpy]

Photon-phonon interactions are daily life in semiconductors, especially the ones (GaAs and many more) where some phonons are polar. Some phonons there have also frequencies in the IR spectrum.

 

Even with silicon, temperature is commonly measured from distance by comparing Stokes and anti-Stokes intensity of Raman scattering.

 

Due to slower sound propagation, a few 100MHz achieve acoustic wavelengths similar to light, and this permits to make the equivalent of a diffraction grating, whose pitch determines a diffraction direction. The local index depends on the pressure there.

 

Carbon microphones rely on contact between carbon grains. The tiny contacts concentrate the force, and some phenomena (tunnel, thickness of superficial insulators) must be more sensitive to the force than conductivity is.

 

A recent research paper describes a piezo antenna. I suppose that the mechanical resonance lets more charges move with a bigger displacement. Anyway, piezo materials are commonly used from <20Hz to >>1GHz in electric circuitry, which is an interaction with photons. Interation with free photons as in that antenna looks newer.

 

QM has no direct answer to "photon-phonon interaction". Someone can try to model the behaviour of a given material like GaAs or quartz or BaTiO₃, and then he'll naturally do it within QM. More generally, QM itself doesn't tell "a particle behaves like this". Additional modelling is needed; for instance that an electron is sensitive to electric fields due to its charge, but sometimes the magnetic field matters due to the magnet quantum, sometimes gravity too due to the mass, and maybe a fifth force exist that we still ignore, so "the electron's Hamiltonian" is a misleading expression. Same for photons and phonons.

[OptimisticCynic]

Here is an entertaining application:

https://en.wikipedia.org/wiki/Music_On_A_Long_Thin_Wire