Ultra-Short Pulse Biphoton Source in Lithium Niobate Nanophotonics at 2$\text{\mu}$m

TL;DR

This paper demonstrates a femtosecond biphoton source in lithium niobate nanophotonics at 2 micrometers, achieving ultrabroad bandwidths and high brightness, advancing ultrafast quantum information processing.

Contribution

It introduces the first dispersion-engineered lithium niobate nanophotonic biphoton source with femtosecond pulses and ultrabroad bandwidths, enabling scalable ultrafast quantum photonics.

Findings

Bandwidth of 17 THz centered at 2.09 μm

Brightness of 8.8 GHz/mW

Potential for ultrafast nanophotonic quantum information processing

Abstract

Photonics offers unique capabilities for quantum information processing (QIP) such as room-temperature operation, the scalability of nanophotonics, and access to ultrabroad bandwidths and consequently ultrafast operation. Ultrashort-pulse sources of quantum states in nanophotonics are an important building block for achieving scalable ultrafast QIP, however, their demonstrations so far have been sparse. Here, we demonstrate a femtosecond biphoton source in dispersion-engineered periodically poled lithium niobate nanophotonics. We measure 17 THz of bandwidth for the source centered at 2.09 \textmu m, corresponding to a few optical cycles, with a brightness of 8.8 GHz/mW. Our results open new paths towards realization of ultrafast nanophotonic QIP.