
A chip-integrated coherent photonic-phononic memory - T-zex
https://www.nature.com/articles/s41467-017-00717-y
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sounds
tl;dr eli5:

This is research into photonic (optical fiber) links and how to store several
different colors (frequencies) in a vibrating material. The vibrating material
is still a transmission but because it to 100,000x slower than light, it
represents "storage."

(In case you are confused, this research is just about the storage, and not
the optical link.)

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pc2g4d
"Controlling and manipulating quanta of coherent acoustic
vibrations—phonons—in integrated circuits has recently drawn a lot of
attention, since phonons can function as unique links between radiofrequency
and optical signals, allow access to quantum regimes and offer advanced signal
processing capabilities. Recent approaches based on optomechanical resonators
have achieved impressive quality factors allowing for storage of optical
signals. However, so far these techniques have been limited in bandwidth and
are incompatible with multi-wavelength operation. In this work, we
experimentally demonstrate a coherent buffer in an integrated planar optical
waveguide by transferring the optical information coherently to an acoustic
hypersound wave. Optical information is extracted using the reverse process.
These hypersound phonons have similar wavelengths as the optical photons but
travel at five orders of magnitude lower velocity. We demonstrate the storage
of phase and amplitude of optical information with gigahertz bandwidth and
show operation at separate wavelengths with negligible cross-talk."

Definitely don't follow this!

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dogma1138
Basically they found a way to store the exact peroperties of a light signal in
a sound wave.

This means that the quanta of light can be stored in another form and then I
assume reconstructed in a reverse process.

This means that the entire information that is stored in it is preserved
rather than a sampled approximation.

This sounds like an acoustic delay element (used in electronics, primarily
analog electronics for video/audio and other analog signal processing voodoo
boxes) for optics.

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oakwhiz
Opto-acoustic delay line memory?

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deepnotderp
So they're converting light into phonons and back and using the slower
propagation of phonons as a buffer in an otherwise photonic processor? Clever!

For those wondering, phonons are lattice vibration quasiparticles, they aren't
elementary particles.

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QAPereo
To anyone without a physics background, And just in case the phrase lattice
vibration quasiparticle doesn't leap out of you, by way of analogy consider
ripples in a pond. Particles are well-defined ripples which propagate while
virtual particles our secondary effects of interaction between particles or
the background "water" itself. Meanwhile quasiparticles in this case are
things which behave very much like the first kind of ripple, within the
context of a solid crystal lattice.

