Some commentators say the 21st century will be the ‘age of the electron’. But in computing/communications, the photon has long been displacing the electron. This 17-page note gives an overview. It matters as moving data is 50-90% of data center energy use. We contrast fiber vs copper; and explore AI power, optical computing, and a boom for laser photonics?!
Information travels through fiber optic cables via laser pulses (photons) and through copper cables via electrical pulses (waves of excitation between electrons). Competition is intensifying.
Since 1977, when the world’s first fiber-optic cable was installed, photons have been displacing electrons in long-distance data transmission. Today, fiber is displacing copper cables for the rack-to-rack links within data-centers. And in the future, could GPUs even shift towards optical computing? (i.e. photons over electrons, once again).
The purpose of this 17-page note is to understand the growing competition here – fiber vs copper, photons vs electrons – going all the way back to first principles, as a concise overview for decision-makers.
Particle physics. Electrons are fermions. Photons are bosons. What this means and why it matters is covered on page 2.
Laser photons, in particular, have unique properties (coherent, monochromatic, unidirectional) and applications, as covered on page 3.
How do lasers work? The theory, functioning and an overview of the $20bn pa global laser market are discussed on pages 4-5.
How do fiber optic cables work, what do they cost, and why is it so much more efficient to move laser photons in cables than moving electricity or gas molecules? Answers are re-capped on pages 6-7.
How much energy is needed to move laser photons through fiber, versus moving electrons through copper? Attenuation rates, decibels and real-world fiber energy consumption are covered on pages 8-10.
Fiber vs copper are compared on energy consumption, bitrates, bandwidth-distance and costs on pages 11-13.
Optical computing is the proposal of using photons for data-processing as well as for data-transmission. Fascinating results from recent technical papers are summarised on page 14.
Implications are discussed for the energy demands of AI on page 15, and for long-term global copper consumption on page 16.
Leading companies in laser photonics and fiber are briefly discussed, including three stand-out US pure-plays, on page 17.