Graphene Brings Photodetectors to the Brink of Terahertz Speeds

The article closes with a couple example uses. Basically any place where a fast/efficient conversion between light and electricity is useful could potentially be made better.

Faster cameras are certainly possible, but most cameras are slowed down by processor and storage, not the sensor. As an example of this, Vision Research sells a 4k model of the Phantom high-speed camera, which does 940 fps at 4096x2304. And they've got 4 different models that will do 640x480 video at 34,700 - 69,900fps. That's 10-20 billion pixels every second, or 45-90 gigabytes/second raw color video data, which is significantly faster than you can write to RAM in most computers.

But at 1,000,000,000,000+fps as the article talks about? Awesome innovation, communications look to be a winner here.