The future of high-speed computing: CPUs with optics

[gvazdas]

https://arstechnica.com/science/2019/04/the-future-of-high-speed-computing-may-be-larger-cpus-with-optics/?fbclid=IwAR0xy5zfEbwKJDNjTLZ5FSYtOXQMA4qrKO1Dxzs0scs4WwmtudgAvjQptMA

Light carries the information, but switching is performed electronically. Essentially, the light has to be absorbed to generate a current. The generated current is then used to modulate another optical signal to create an optical transistor.

The researchers managed to transmit data at 40Gb/s, which is about standard for a high-capacity multiwavelength link.

Chips are going to get larger. In the not-so-distant future, it will make sense to move certain functions to computational units based on these hybrid optical transistors. But not all of them—if a Core i7 processor (1.9 billion transistors) were to be implemented optically, the chip would have an area of 48m2.

[Archangel125]

If the absorption of light itself generates the current they use to translate the signal, doesn't that imply a photosensitive chemically-treated surface that must, inevitably, lose sensitivity over time?

[bitches]

Plain metal can achieve the photoelectric effect without coatings. It's a subject that has been studied since the 1920s; it probably isn't going to be a roadblock to this new research.

[gvazdas]

You don't need conventionally photosensitive materials, all materials have a resonant EM frequency. Shoot the right wavelength at the right material and you'll be able to excite something.

[hexpunK]

Optical processors have been around for a bit now, a place I worked with like 3-4 years ago for my degree was looking into getting some units in to augment their on-site UV2000 cluster. Massively parallel things with shitloads of throughput like an Optical CPU would in theory be baller as fuck for their workload of genomics. Multi-terabyte datasets are common, and even a cluster can take a long time to chomp through that.

No idea if they ever managed to get their hands on any, but the head of the computing facility sold me on the idea at the very least