Reversible Computation in Integrated Photonics

Yanbing Young Zhang

Jonathan Lavoie, Blair Morrison

Ben Haylock

Herewithin we present multiplexed integrated photonics as a realisable route to large-scale quantum technologies. Quantum photonics is one many platforms for experimental demonstrations of quantum information science. The technological advantages afforded by the combination of integrated photonic circuits with multiplexing techniques can enable performance enhancements to make photonics a leading infrastructure for implementation of real-world quantum information systems. For this purpose, we create integrated circuits to solve technical challenges in the fields of quantum cryptography, discrete variable and continuous variable quantum computation. These circuits were fabricated in a facility developed at Griffith University, Centre for Quantum Dynamics, for the production of annealed and reverse proton exchange waveguides in congruent lithium niobate and have found applications across the fields of quantum optics and cryptography. We develop and demonstrate the first integrated many-mode active optical demultiplexing of single photons from a solid-state source. This scheme enables the production of a multiphoton Fock state across multiple spatial modes from a single high brightness solid-state source with temporal indistinguishability. This work addressed a major hurdle in the development of photonic quantum computers, namely generation of a large number of indistinguishable single photons on demand. To perform the demultiplexing of single photons we develop two key technologies; a high-speed 1:4 integrated photonic switch and a many channel arbitrary pulse sequence generator. Cryptography as a field is increasingly reliant on quantum random number generators for added security. With increased demand comes a requirement for higher bitrate random number generators, and as such we demonstrate multiplexing of a random number generation scheme based on measurements of quantum vacuum fluctuations. Furthermore, we show an increased level of security at high bitrates by implementing a new signal processing scheme We demonstrate integrated generation, manipulation and homodyning of squeezed light on a single chip for the first time. This scheme is the first successful demonstration of full integration of all the major components needed for continuous variable quantum computation in a temporally multiplexed architecture. These results represent contributions to several fields of study, demonstrating the advantages of integrated quantum photonic multiplexing, and are of interest to the quantum computing, information security, integrated optics, and electronic control communities.

Jiakun He, Bryn A. Bell, Alvaro Casas‐Bedoya +4 more

Integrated sources of indistinguishable photons have attracted a lot of attention because of their applications in quantum communication and optical quantum computing. Here, we demonstrate an ultra-compact quantum splitter for degenerate single photons based on a monolithic chip incorporating Sagnac loop and a micro-ring resonator with a footprint of 0.011 mm2, generating and deterministically splitting indistinguishable photon pairs using time-reversed Hong-Ou-Mandel interference. The ring resonator provides enhanced photon generation rate, and the Sagnac loop ensures the photons travel through equal path lengths and interfere with the correct phase to enable the reversed HOM effect to take place. In the experiment, we observed a HOM dip visibility of 94.5 +- 3.3 %, indicating the photons generated by the degenerate single photon source are in a suitable state for further integration with other components for quantum applications, such as controlled-NOT gates.

Jonathan C. F. Matthews, Alberto Politi, André Stefanov +14 more

Faten Ouaja Rziga, Kamel Besbes

Quantum mechanics is the revolution in thinking of the 20th century and will be the revolution in various applications in the 21st century. The world's powers-that-be each have their own particular or common quantum plans to access these new technologies. Indeed, emerging quantum computing technologies are poised to replace classical binary logic. The development of new integrated operators, on subatomic circuits, will benefit from an exponential reduction in size, power consumption and fantastic computing capacity. Indeed, the quantum circuit is proving day by day a very high level of numerical computation disrupting communication, encryption and modelling algorithms. However, what about the reversibility of quantum operators in order to adapt them to our already widely used classical computers?Current design flows will be challenged at various levels both in terms of computer-aided design (CAD) methods and in all major aspects of quantum computing circuit design, including logic synthesis, simulation, verification and testing. On the other hand, quantum technology remains dependent on access to integrated photonics and probably on the integration of algorithms in hyper-flexible photon electron hardware. Our paper intends to present the possibility of designing classical operators based on quantum operators in order to explain and explore the mixed Qbit-Bit Using the IBM simulator, to analyse their functions, to design new electronic functions and to implement them in quantum circuits.