3 ms·

Would this work on peanuts? "Near-Field Optical Nanopatterning of Graphene" (2025) https://onlinelibrary.wiley.com/doi/10.1002/smsc.202500184 https://onlinelib

• PaulHoule 11mo ago
  Most lasers have a relatively small rate of gain per unit length so they depend on mirrors. Some lasers like https://en.wikipedia.org/wiki/Nitrogen_laser https://en.wikipedia.org/wiki/Nitrogen_laser get enough gain that you can don’t need the mirrors —- it’s pretty easy to build one about a foot long that can make nanosecond pulses that are about as long as the laser. Random lasers uses random particles to extend the optical path instead of mirrors https://en.wikipedia.org/wiki/Random_laser https://en.wikipedia.org/wiki/Random_laser I studied condensed matter physics and knew a professor well who was one of Anderson’s grad students so the phenomenon of https://en.wikipedia.org/wiki/Anderson_localization https://en.wikipedia.org/wiki/Anderson_localization which is relevant to random lasers is familiar to me.
  • pfdietz 11mo ago
    There was an old (50 years ago!) Amateur Scientist in Scientific American on how to make your own nitrogen laser. https://www.jstor.org/stable/24950104 https://www.jstor.org/stable/24950104 That column had all sorts of homemade lasers. CO2, helium-neon, dye lasers...
    • bigiain 11mo ago
      Oh man, I miss my dad's collection of a decade or two's worth of Scientific American magazines. When I was a kid in the 70s/80s, they were pure intellectual magic to me.
      • pfdietz 11mo ago
        There was a CD (or two?) of all the Amateur Scientist columns. It may still be available through Amazon.
  • westurner 11mo ago
    Cool field! Anderson localization ... wavefronts /?hnlog wavefro - Huygens-Steiner ; https://news.ycombinator.com/item?id=43673759 https://news.ycombinator.com/item?id=43673759 , https://news.ycombinator.com/item?id=44401685 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 https://www.nature.com/articles/s41467-021-24493-y ... citations: https://scholar.google.com/scholar?cites=6348012568124728820&as_sdt=5,43&sciodt=0,43&hl=en 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&as_sdt=5,43&sciodt=0,43&hl=en 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://opg.optica.org/oe/fulltext.cfm?uri=oe-33-19-41011 .. https://news.ycombinator.com/item?id=45620981 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 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 https://news.ycombinator.com/item?id=41643024 - /?hnlog metamaterial From https://news.ycombinator.com/item?id=45715228 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://www.nature.com/articles/s41586-025-09054-3 .. https://news.ycombinator.com/item?id=45236896 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 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 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 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 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 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/adfm.202511015 https://advanced.onlinelibrary.wiley.com/doi/abs/10.1002/adf... https://westurner.github.io/hnlog/#comment-45951285 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/891867c0466b .. https://gemini.google.com/share/dece8f932e69 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 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://www.science.org/doi/10.1126/science.adw2025 .. https://news.ycombinator.com/item?id=45772158 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.202520907 https://advanced.onlinelibrary.wiley.com/doi/10.1002/adfm.20... .. https://news.ycombinator.com/item?id=45772190 https://news.ycombinator.com/item?id=45772190