imec: AI data centers need optical interconnects scaling to 3.2T

imec's report on scaling optical interconnects for AI says copper links are hitting fundamental limits in reach and power efficiency. The industry is moving from 800G to first 1.6T transceivers on silicon photonics, targeting 3.2 Tbps by the end of the decade with LiNbO₃ and LiTaO₃ integrated via micro-transfer printing.

• Copper links stay efficient only over distances of about a millimeter
• First 1.6T transceivers at 200 Gbps per lane are approaching sampling
• 3.2T goal requires modulators with bandwidth beyond 100 GHz
• XPO concept targets up to 12.8T but needs liquid cooling