On-chip pulse shaping of entangled photons

TL;DR

This paper demonstrates on-chip spectral shaping of entangled photons using a silicon photonic pulse shaper, enabling precise control of quantum states for advanced quantum information processing.

Contribution

First demonstration of biphoton pulse shaping with an integrated spectral shaper, achieving line-by-line phase control on a 3 GHz grid for high-dimensional entangled states.

Findings

Achieved spectral phase control on a 3 GHz grid.

Observed biphoton temporal features matching theoretical predictions.

Enabled manipulation of high-dimensional entangled quantum states.

Abstract

We demonstrate spectral shaping of entangled photons with a six-channel microring-resonator-based silicon photonic pulse shaper. Through precise calibration of thermal phase shifters in a microresonator-based pulse shaper, we demonstrate line-by-line phase control on a 3~GHz grid for two frequency-bin-entangled qudits, corresponding to Hilbert spaces of up to $6\times 6$ ($3\times 3$) dimensions for shared (independent) signal-idler filters. The pulse shaper's fine spectral resolution enables control of nanosecond-scale temporal features, which are observed by direct coincidence detection of biphoton correlation functions that show excellent agreement with theory. This work marks, to our knowledge, the first demonstration of biphoton pulse shaping using an integrated spectral shaper and holds significant promise for applications in quantum information processing.