Electrically-programmable frequency comb for compact quantum photonic circuits

Shakir Ullah; Mehmet Emre Tasgin; Rasim Volga Ovali; Mehmet Günay

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arXiv · 2308.00439

Electrically-programmable frequency comb for compact quantum photonic circuits

Shakir Ullah·Mehmet Emre Tasgin·Rasim Volga Ovali·Mehmet Günay

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Abstract

Recent efforts have demonstrated the first prototypes for compact and programmable photonic quantum computers (PQCs). Utilization of time-bin encoding in loop-like architectures enabled programmable generation of quantum states and execution of different (programmable) logic gates on a single circuit. Actually, there is still space for better compactness and complexity of available quantum states and gate operations: a photonic circuit (PC) can operate at multiple frequencies. Here, we propose an electrically-programmable frequency comb that generates continuously tunable entanglement among different frequencies. The device is not directly integrated into fragile quantum processing components but is to be used as a fast (picoseconds) tunable auxiliary source provided into state-of-the-art measurement-induced loop-based photonic quantum computers employing programmable (50 MHz) beam-splitters (BSs) and phase-shifters. Multimode entanglement generation is controlled via Fano resonance in the nonlinear response. The generated entanglement can be tuned continuously via an applied voltage which can be delivered to the device via nm-thick wires. The proposed device is integrable, CMOS-compatible, and operates below ps but is limited with transistor clock speeds 5-100 GHz.

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BibTeX RIS

Shakir Ullah, Mehmet Emre Tasgin, Rasim Volga Ovali, Mehmet Günay. 2023-08-01. Electrically-programmable frequency comb for compact quantum photonic circuits. https://arxiv.org/abs/2308.00439

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