EPFL Shows Chip That Turns Millimeter Waves into Light at 67% Efficiency

At a glance

Researchers at Switzerland's EPFL demonstrated a chip-sized device that converts millimeter waves, high-frequency radio signals, into optical light signals used in fiber communication. The device converted 67% of its internal signal into light.

Key points

1. 1

   The team built two small light resonators on a thin lithium niobate film.

2. 2

   These resonators were aligned with a sub-millimeter metal resonator so the two signals overlap well.

3. 3

   The 67% figure is internal efficiency, and total efficiency including wireless coupling is very low.

4. 4

   The team says switching to superconducting materials could reduce losses.

Why it matters

Connecting quantum computer chips over optical fiber requires turning radio-frequency signals into light. This work shows a way to build that link on a chip.