How to Shape a Single Photon

S. D. Barrett

Joerg Bochmann, Holger Specht, Martin Muecke +5 more

Axel Kuhn

Сыч Денис Васильевич, Valentin Averchenko

Abstract Single-pixel imaging is a method for obtaining an image without multi-pixel sensors. In this method, an object of interest is illuminated by light that has specifically designed spatio-temporal shape, while a single-pixel detector measures the total amount of reflected or transmitted light. The key prerequisite of this method is the ability to create a given spatio-temporal light shape, which becomes especially challenging at the level of single photons. The current photon shaping procedures cannot be directly applied to single-pixel imaging due to the limited generation rate or the need for post-processing. In this work, we propose a highly efficient method for generating arbitrary single-photon shapes without post-selection. We exploit the heralded single-photon shaping approach, and study the effect of the modal properties of a single-photon detection on the characteristics of the heralded photon. We find that the use of multi-mode detection allows to increase the heralding probability of shaped photons proportionally to the number of detected modes while keeping the shape intact, which makes it highly desirable for single-pixel quantum imaging.

Kahraman G. Köprülü, Yu-Ping Huang, Geraldo A. Barbosa +1 more

Using spontaneous optical parametric downconversion, we experimentally demonstrate heralded generation of shaped single photons, whose modes are tailored indirectly by applying amplitude modulation on the pump field that drives the downconversion process. Our experiment opens a door to creating high-quality, mode-shaped single photons at a substantially higher efficiency than is possible with the existing method of direct single-photon shaping.

Xue Dong, Re-Bing Wu

The transmission of flying qubits carried by itinerant photons is fundamental in quantum communication networks. To physically match the receiver system, the single photons must be prepared in proper shapes, and this leads to a variety of flying-qubit control problems. In this paper, we introduce the optimal control theory to the shaping of single photons, where the control to be optimized are coherent driving fields. We design gradient-based algorithms to minimize the shape difference between the emitted and desired single photons. Simulation results show that the optimization can achieve high-fidelity in the generation of decaying photon shapes with a two-level atom. However, its performance is limited and hence has to be combined with incoherence controls when the target shape has a rising part.