4 ms·
Sorry, but how does one create a transistor from a superconductor? Maybe I’m missing something here.
by jakeinspace 3y ago
Sorry, but how does one create a transistor from a superconductor? Maybe I’m missing something here.
- bpye 3y agoI don’t think we’d necessarily have to use it for transistors, but could use it in place of the metal interconnect that is significant in terms of resistive loss.
- junofan 3y agoI think Josephson junctions. Also maybe you could eliminate copper loss by using LK-99 interconnect layers.
- floxy 3y agoMost superconducting logic families aren't using transistors at all. They use Josephson junctions, which are just two pieces of superconductor separated by a non-supercondutor. RSFQ (Rapid Single Flux Quantum) uses millivolt-high picosecond-long pulses to represent logic 1 and their absence as logic zero, instead of using voltage level as in CMOS. https://ieeexplore.ieee.org/document/783712 https://ieeexplore.ieee.org/document/783712 (770 GHz toggle flip-flop in 1999) https://www.physics.sunysb.edu/Physics/RSFQ/Projects/WhatIs/rsfqre2m.html https://www.physics.sunysb.edu/Physics/RSFQ/Projects/WhatIs/...
- Culonavirus 3y agoSooo, a 770 GHz processor? Do I understand it correctly? Jesus.
- yetihehe 3y agoIf using that flip-flop, whole processor will be closer to 100ghz (typically there are multiple transistors which need to stabilise before you have a result of computation). But probably those superconductors could enable even faster transistors and maybe we could get 1THz processors.
- aitchnyu 3y agoLike IDE ribbon cables gave way to sleek SATA cables, we could have another parallel to serial transition from silicon multicore crap to superconducting single core.
- jacquesm 3y agoNo, you'll get superconducting multicore because all that will happen is that the bloat will expand to consume the new cycle budget. This has already happened many times.
- dtx1 3y agoI'm looking forward to Chromium version 4201337 needing 20% of my 1Thz CPU to render simple text.
- regularfry 3y agoWe'll get superconducting multicore because as a first step everyone will just map what they already know to the new space. Which is fun.
- MayeulC 3y agoI suspect you'd still need very low temperatures to make this work, even with a high temperature superconductor: low temperatures reduce thermal noise, which may be an issue at such time scales (unless you pump a lot of energy per bit, which means high voltages (limits scaling) or current/capacitances (also limits scaling).
- jakeinspace 3y agoAre you aware of any obvious issues with manufacturing Josephson junctions using photolithography? Like, would switching to an LK-99 or similar set us back to the 70s in terms of wafer density/size?
- floxy 3y agoYou might be interested is this video, which talks about the EDA issues for RSFQ logic: https://www.youtube.com/watch?v=3O6GpFCIxv0 https://www.youtube.com/watch?v=3O6GpFCIxv0 ...and... https://en.wikipedia.org/wiki/Josephson_junction_count https://en.wikipedia.org/wiki/Josephson_junction_count
- rezonant 3y agoWell you can apparently make diodes with them: https://scitechdaily.com/mit-develops-superconducting-device-to-radically-cut-energy-use-in-computing/?expand_article=1 https://scitechdaily.com/mit-develops-superconducting-device...