On-chip electrical control of nonlinear quantum optics using a quantum dot in a waveguide

Jing Zhang, Re-Bing Wu

D. Hallett, Andrew P. Foster, David L. Hurst +7 more

The generation of indistinguishable single photons and control of photon-photon interactions are key requirements for photonic quantum networks. Nano-photonic waveguide-based architectures, in which few-level solid state systems provide both single photon generation and the nonlinearity through which two or more photons interact, offer a scalable route to such networks. However, it is a challenge to maintain the optical quality of the embedded photon sources whilst also providing fine-tuning of the emission frequency and optical nonlinearity in a waveguide geometry. We demonstrate a tunable solid-state platform for scalable photonic quantum networks which allows local electrical control of both single photon generation and optical nonlinearity at the single photon level. Electrical tuning and switching of coherent photon scattering from a quantum dot embedded in a nano-photonic waveguide is demonstrated, with a transmission extinction as large as 40±2% measured on resonance. Observation of a clear, voltage-controlled bunching signal in the photon statistics of the transmitted light demonstrates the single photon character of the nonlinearity. The deterministic nature of the nonlinearity is particularly attractive for the future realization of photonic gates for scalable nano-photonic waveguide-based quantum information processing.

Matthew A. Pooley, Raj B. Patel, A. Boyer de la Giroday +8 more

Dominic Hallett, Andrew P. Foster, David L. Hurst +7 more

Local control of the generation and interaction of indistinguishable single photons is a key requirement for photonic quantum networks. Waveguide-based architectures, in which embedded quantum emitters act as both highly coherent single photon sources and as nonlinear elements to mediate photon-photon interactions, offer a scalable route to such networks. However, local electrical control of a quantum optical nonlinearity has yet to be demonstrated in a waveguide geometry. Here, we demonstrate local electrical tuning and switching of single photon generation and nonlinear interaction by embedding a quantum dot in a nano-photonic waveguide with enhanced light-matter interaction. A power-dependent transmission extinction as large as 40$\pm$2% and clear, voltage-controlled bunching in the photon statistics of the transmitted light demonstrate the single photon character of the nonlinearity. The deterministic nature of the nonlinearity is particularly attractive for the future realization of photonic gates for scalable nano-photonic waveguide-based quantum information processing.

Alexandre Enderlin, M. Ravaro, V. Voliotis +2 more

Hallett, D., Foster, A., Hurst, D. +7 more

Quantum photonics is a rapidly developing platform for future quantum network applications. Waveguide-based architectures, in which embedded quantum emitters act as both nonlinear elements to mediate photon–photon interactions and as highly coherent single-photon sources, offer a highly promising route to realize such networks. A key requirement for the scale-up of the waveguide architecture is local control and tunability of individual quantum emitters. Here, we demonstrate electrical control, tuning, and switching of the nonlinear photon–photon interaction arising due to a quantum dot embedded in a single-mode nano-photonic waveguide. A power-dependent waveguide transmission extinction as large as 40±2% is observed on resonance. Photon statistics measurements show clear, voltage-controlled bunching of the transmitted light and antibunching of the reflected light, demonstrating the single-photon, quantum character of the nonlinearity. Importantly, the same architecture is also shown to act as a source of highly coherent, electrically tunable single photons. Overall, the platform presented addresses the essential requirements for the implementation of photonic gates for scalable nano-photonic-based quantum information processing.