Memories are about density. I my memory isn't playing tricks with me, a TCAM is about ~300-400F^2 where F is the feature size of the node. On a per bit level, that means that this bit is 4E^10 bigger.

Put another way, the TLB in a CPU is relatively small and definitely a hotspot but you could estimate the TLB in a CPU at ≈ 0.0003 – 0.002 mm^2. which is ~50 times smaller then the single bit in this paper. To get to 10GHz we could just make 10 copies of an existing TLB operating at 1GHz and still have a ton of headroom. There is also a electro-optical conversion penalty that you need to take into account with most optical systems.

Not trying to be a Debbie downer. It's a cool result, no doubt incredibly useful for fully optical systems. Probably something really useful here for optical switching at the datacenter infrastructure level.