A Quantum Pulse Gate based on Spectrally Engineered Sum Frequency Generation

TL;DR

This paper proposes a quantum pulse gate based on spectrally engineered sum frequency generation in a PPLN waveguide, enabling selective access and conversion of broadband spectral modes of ultrafast quantum light for quantum information applications.

Contribution

It introduces a novel implementation of a quantum pulse gate using spectral engineering in SFG, allowing mode-selective manipulation of ultrafast quantum states.

Findings

High-efficiency mode selection demonstrated

Spectral broadband modes can be individually addressed

Potential for advanced quantum information processing

Abstract

We introduce the concept of a quantum pulse gate (QPG), a method for accessing the intrinsic broadband spectral mode structure of ultrafast quantum states of light. This mode structure can now be harnessed for applications in quantum information processing. We propose an implementation in a PPLN waveguide, based on spectrally engineered sum frequency generation (SFG). It allows us to pick well-defined spectral broadband modes from an ultrafast multi-mode state for interconversion to a broadband mode at another frequency. By pulse-shaping the bright SFG pump beam, different orthogonal broadband modes can be addressed individually and extracted with near unit efficiency.