Optical Revolution On the Horizon: Hollow Core Fibre Matures - Part 1

Hollow core fibre has been around a long time. Early versions had really high optical loss of 1 db/km, but speeds close to what light travels in a vacuum (299,792, kilometers per second) versus approximately 200,000 kilometers per second in solid core fibre. The high optical loss limited deployment to very short links deployed for low latency trading. Firms like Jump trading have installed hollow core fibre from their microwave towers into financial exchange data centers like the CME facility in Aurora, Illinois. EUNetworks has deployed it in the London metro to connect financial exchange trading points. In hollow core the light tends to quickly scatter and bounce around so optical intensity fades very quickly. In solid core scattering is far less so the transmission rates are much greater at the price of a big latency penalty. The other drawback is manufacturing and cost. Solid core draws molten glass and allows gravity to shape into a strand. We can't do that with hollow core. As a result, hollow core is many multiples the cost of solid core.

But the potential is huge. Networks are centered around resiliency, latency, and bandwidth. That is the Holy Trinity or Trimurti (the three manifestations of Brahman in Hinduism) of layer 1 optical networks. Another factor is chromatic dispersion in solid core fibre. The fact that light frequencies move at different speeds through solid glass requires compensation in the form of digital processing to keep the bit rate at acceptable levels (one error per billion bits or less). But light traveling through air in hollow glass experiences negligible chromatic distortion. So the development road map is quite clear, namely get the optical loss down to levels comparable to standard fibre and scale up production to get those wonderful economies of scale. Then we can have an Optical Revolution and maybe a party too to celebrate. While solid core fibre has been generally limited to the C band (4 to 6 THz), solid core works over the much broader range of 66 THz.

Hollow core fibre enjoying the same manufacturing cost and bandwidth of standard G.652d solid core fibre would be a revolution. It would be deployed in standard long haul networks to harvest a 31% reduction in latency. In fact, the first carriers to deploy it would disrupt the industry and take a commanding lead in market share. There is a clear entrepreneurial opportunity here.