Manipulating Quantum Waveform of Entangled Photons

Harald Weinfurter

John M. Donohue, Michael D. Mazurek, Kevin J. Resch

The optimal properties for single photons may vary drastically between different quantum technologies. Along with central frequency conversion, control over photonic temporal waveforms will be paramount to the effective coupling of different quantum systems and efficient distribution of quantum information. Through the application of pulse shaping and the nonlinear optical process of sum-frequency generation, we examine a framework for manipulation of single-photon waveforms. We use a nonperturbative treatment to determine the parameter regime in which both high-efficiency and high-fidelity conversion may be achieved for Gaussian waveforms and study the effect such conversion techniques have on energy-time entanglement. Additionally, we prove that aberrations due to time ordering are negligible when the phase matching is nonrestrictive over the input bandwidths. Our calculations show that ideal quantum optical waveform conversion and quantum time lensing may be fully realized using these techniques.

Zhen-Sheng Yuan, Xiao‐Hui Bao, Chao‐Yang Lu +3 more

Hui Yan, ShiLiang ZHU, Kai-Yu Liao +1 more

Manipulation of the temporal waveform of single photons not only provides a powerful benchmark tool for fundamental research in quantum physics, but also plays a critical role in quantum information processing. The generation of narrowband paired photons makes it possible for manipulating the temporal waveform of single photons. At first, we reviewed the generation of narrowband photon pairs through four wave mixing and slow light with high optical depth cold atoms. Secondly, we reviewed the generation and manipulation of the heralded narrowband single photons with controllable waveforms. Thirdly, we reviewed the application of the heralded narrowband single photons: (1) single photon precursor; (2) the coherent interaction between the heralded narrowband single photon and two energy level atoms; (3) DPS quantum key distribution with the heralded narrowband single photons.

Hiroko Tomoda, Yu Nishizawa, Akihiro Machinaga +7 more

A versatile quantum light source capable of programmably generating a variety of quantum light is a key enabler for photonic quantum technologies. In particular, independent control over both the output quantum state and its temporal waveform is essential for realizing diverse functionalities and enhancing processing performance. However, conventional sources of optical non-Gaussian states, a crucial resource for photonic quantum information processing, typically emit fixed states with predetermined temporal waveforms, lacking their programmability. Here, we propose a programmable non-Gaussian quantum light source that offers independent and arbitrary tunability of both the quantum state and the temporal waveform within a single platform. As a distinctive feature, our approach employs a heralding scheme in which these two properties are indirectly engineered to user-defined targets by manipulating the light in the heralding channel, thereby avoiding optical losses associated with direct manipulation of the heralded quantum light. We develop a prototype and demonstrate the generation of single-photon, Schrödinger cat, and two-photon states in a variety of unconventional temporal waveforms without degradation in state quality. This platform provides a versatile tool for tailoring quantum light to specific applications, significantly expanding the capabilities of photonic quantum technologies.

Anton Zeilinger