Of those you mention, Meta, Microsoft, and Google are dumping Billions into AI data centers. In addition to the chips from NVIDIA and AMD they also need the equipment to utilize the power of the chips.
In term of the high-speed connectivity solutions needed, CRDO Tech (Credo) and Astera Labs (ALAB) are the best; CIEN (Ciena) is a Monster in various areas of AI networking.
(and for Quantum Computer fans, Rigetti will soon release a 100+ qubit system- I love this one, and hope my love is not in vain,,,)