Abstract: In the era of digitally connected world and recent advancement of quantum computing technology, absolutely unpredictable random numbers are a necessity for cryptography in banking and financial sectors, secure communication, modeling, gaming applications etc. It has been known and widely accepted that the random numbers generated out of the principle of quantum mechanics, i.e., quantum random numbers, can provide indisputable randomness. Over the past two decades, researchers have explored and developed a wide range of techniques to generate this resource both in bulk optics and integrated photonics platforms. The CMOS fabrication process compatible silicon photonics technology platform is the most popular for compactness, scalability and integrability with electronic driver and readout circuits. However, in Quantum Random Number Generators (QRNGs), elimination of classical noises using a systematic classical noise cancellation methodology has not been developed so far, and is indeed challenging for harvesting quantum entropy with its fullest capacity. In this talk, we will discuss about the demonstration of a real-time high-speed multi-channel QRNG device, using a programmable photonic integrated circuit (PPIC) in silicon photonics platform. Broadband random fluctuations of quantum photonic waveguide vacuum mode is harnessed in each of the mutually independent channels, by mixing a guided coherent laser light operating at 1550 nm. All classical noises arising out of electrical, mechanical, thermal disturbances etc. associated with the laser light local oscillator, are eliminated by the use of homodyne detection technique and appropriate programming of the photonic integrated circuit. Along with the method of systematic classical noise elimination, we will also discuss about an appropriate theoretical model, which is shown to be validated by experimental observations.

Event Details
Title: Multi-Channel High-Speed Quantum Random Number Generation using a Programmable Photonic Integrated Circuit
Date: February 17, 2026 at 03:00 PM
Venue: ESB234 / Google Meet (https://meet.google.com/rho-bjfd-azx)
Speaker: Mr. Ankan Gayen (EE19D200)
Guide: Dr. Bijoy Krishna Das
Type: PHD seminar

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