Random lasers from peanut kernel doped with birch leaf–derived carbon dots

https://www.jstor.org/stable/24950104

That column had all sorts of homemade lasers. CO2, helium-neon, dye lasers...

Anderson localization ... wavefronts

/?hnlog wavefro

- Huygens-Steiner ; https://news.ycombinator.com/item?id=43673759 , https://news.ycombinator.com/item?id=44401685

(The other Huygens principle is that each point on a wavefront causes another wavefront. How does that also apply to Anderson localization and optical singularities?)

- optical singularities:

"Engineering phase and polarization singularity sheets" (2021) https://www.nature.com/articles/s41467-021-24493-y ... citations: https://scholar.google.com/scholar?cites=6348012568124728820...

- /? optical singularities and Anderson localization

TIL that optical singularities are robust and about optical vortex capture.

- metamaterials

- /? Anderson localization

"Quantum light transport in phase-separated Anderson localization fiber" citations: https://scholar.google.com/scholar?cites=2109673059927233012...

- /?hnlog Fiber

"Selective excitation of a single rare-earth ion in an optical fiber" (2025) https://opg.optica.org/oe/fulltext.cfm?uri=oe-33-19-41011 .. https://news.ycombinator.com/item?id=45620981

- /?hnlog photon

"Telecom-wavelength quantum teleportation using frequency-converted photons" (2025) https://www.nature.com/articles/s41467-025-65912-8

- /?hnlog like black holes

"Deflection of electromagnetic waves by pseudogravity in distorted photonic crystals" (2023) .. https://news.ycombinator.com/item?id=41643024

- /?hnlog metamaterial

From https://news.ycombinator.com/item?id=45715228 :

> Metamaterials and metasurfaces are probably useful for extreme nonlinear spiking neuromorphic computing with integrated nanophotonics.

> Some optical metamaterials have picosecond phase change latency

I learned that researching how to create a speckle QRNG TRNG.

Phase-change metamaterials are probably faster at whitening photonic speckle random than an FPGA.

"Traceable random numbers from a non-local quantum advantage" (2025) https://www.nature.com/articles/s41586-025-09054-3 .. https://news.ycombinator.com/item?id=45236896 :

> This protocol forms the basis for a public traceable and certifiable quantum randomness beacon that we have launched.

Here's that speckle TRNG design chat: https://gemini.google.com/share/1bb101b39c96 :

> This is the key takeaway: the coherence time of the phonon (mechanical storage) is millions to billions of times longer than the coherence time of the exciton (the optical state), which is typically in the picoseconds. This is precisely why it's so attractive for quantum memory.

Todo

> Resonance: If the plasmon's wavelength fits perfectly into the length of the graphene ribbon (like a guitar string vibrating), you create a strong standing wave. The energy of the THz light is now trapped and massively amplified within this tiny graphene structure.

And also, twisting carbon nanotubes causes a bandgap which may be useful for creating transistors out of carbon.

Nano mechanical energy storage twists SWCNT;

From https://news.ycombinator.com/item?id=45951197 re: "Exploring recent advances in the versatility and efficiency of carbon materials for next generation supercapacitor applications: A comprehensive review" (2025) :

"Giant nanomechanical energy storage capacity in twisted single-walled carbon nanotube ropes" (2024) https://www.nature.com/articles/s41565-024-01645-x

But that's at like 1-10 GHz, not Thz.

(Switching times by material: graphene: ~100s of Ghz; rGO: 1-10 GHz, SWCNT: 1-10 GHz,)

From this design chat about an integrated biorefinery chip fabrication concept, I learned that [Gemini 3 Pro] thinks there's an 80% chance that coating and drying carbon nanotubes in Lignin (or Lignin Vitrimer) would cause a sufficient bandgap in graphene: https://gemini.google.com/share/6796575598b2

> Can graphene be switched at Thz frequencies, to drive optical resonators?

[ You need all-optical switching for Thz frequencies, and also Also there are Graphene Plasmons which can be rescaled]

Which metamaterials are best for Thz all-optical switching? Are there all-carbon options? https://gemini.google.com/share/fe15869a8c9a :

> Graphene metasurfaces; highly oriented pyrolytic graphite (HOPG), Randomly oriented films of SWCNTs

Laser Shockwave Compaction might solve here; but would it destrain the bandgap out of lignin-strained CNT transistors too?

"One‐Step Transformation of Single‐Walled Carbon Nanotube Networks into High‐Performance Multilayer Graphene‐Rich Films via Laser Shockwave Compaction" (2025) https://advanced.onlinelibrary.wiley.com/doi/abs/10.1002/adf... https://westurner.github.io/hnlog/#comment-45951285

...

Are Anderson localization or optical singularities useful for maximizing state coherence time in carbon?

3.5pro: https://gemini.google.com/share/891867c0466b .. https://gemini.google.com/share/dece8f932e69 :

[ Yes, Anderson localization utilizes disorder, and Optical singularities utilize order (topology), and Isotopic Purification creates a "spin vacuum" to minimize magnetic noise ]

> Result: This is how record-breaking coherence times (seconds to minutes) are achieved in NV centers in diamond, far surpassing what Anderson localization alone typically provides

There are newer lower energy processes for fabricating lab grown diamond carbon with NV centers and color centers;

From "Scalable nano positioning of highly coherent color centers in prefab diamond" (2025) https://news.ycombinator.com/item?id=45843416 :

"Rapid, low-temp nanodiamond formation by electron-beaming adamantane C–H bonds" (2025) https://www.science.org/doi/10.1126/science.adw2025 .. https://news.ycombinator.com/item?id=45772158

"Quantum Nanodiamonds from 1 Step, Industrial-Scale Pressure and Temp Process" (2025) https://advanced.onlinelibrary.wiley.com/doi/10.1002/adfm.20... .. https://news.ycombinator.com/item?id=45772190