Experiments in the field of quantum optics often require very low concentrations of dust particles in the laboratory, but the complexity of working routines precludes operation within a proper clean room. Research teams have established a multitude of different approaches, precaution measures, and habits to keep the delicate optics setups free of contamination. Here, we systematically quantify dust particle concentration during day-to-day operation of a quantum optics lab, assess the effectiveness of various measures, and give practical recommendations.
Quantum communication provides high security and privacy, offering effective protection against eavesdropping and decryption during information transmission. Its inherent unconditional security addresses information security issues effectively. Dust particles, as prevalent environmental factors in the atmosphere, exert negative impacts on both traditional and quantum communication. Due to the higher requirements for signal fidelity and stability in quantum communication, the impact of dust particles may be more significant. To investigate the effect of dust aerosol particles on the performance of satellite-ground quantum communication links, we established quantitative relationships between particle number concentration and transmission distance, and the link attenuation, as well as the channel capacity, system survival function, and error rate of three noise channels: amplitude damping, bit-flip, and depolarizing channels. Using Matlab, we conducted experimental simulations based on the size distribution function of dust aerosol particles and Mie scattering theory. The simulation results indicate that when the transmission distance is 6 km and the particle concentration of dust aerosols increases from
20/m3to
55/m3, the channel attenuation factor increases from
84.35dB/kmto
232dB/km. The capacity of the amplitude damping channel decreases from
0.6486bit/sto
0.3943bit/s, and the survival function of the amplitude damping channel decreases to 0.9059. When the particle concentration is
900/m3and the transmission distance increases from 3km to 8km, the bit error rate increases from 0.03 to 0.2. The results indicate that dust aerosols have impacted various aspects of satellite-to-ground communication, each in different ways, highlighting the importance of considering their influence. Therefore, when implementing quantum communication in practice, it is essential to adjust the parameters accordingly to ensure the normal operation of communication.
The main motivation for this paper is to provide a practical guide for the beginners in experimental quantum optics, to save the frustration and make the learning process more streamlined for the novices in the field. This work details the finer points of experiments in the fundamental quantum optics performed using Thorlab’s Quantum Optics Kit. Namely, we detail our observations, interpretations, and subtleties of functioning and arrangement of the experimental setups learned through hands-on experience.
The main motivation for this paper is to provide a practical guide for the beginners in experimental quantum optics, to save the frustration and make the learning process more streamlined for the novices in the field. This work details the finer points of experiments in the fundamental quantum optics performed using Thorlab’s Quantum Optics Kit. Namely, we detail our observations, interpretations, and subtleties of functioning and arrangement of the experimental setups learned through hands-on experience.
At the Physics & Informatics Laboratories (PHI Labs) of NTT Research, Inc., we explore a new principle that will bring about a revolution in information processing technology in the interdisciplinary area between quantum physics and brain science, and it is here where we have positioned our research field.We will focus on quantum-classical crossover physics and critical phenomena in neural networks.We will concentrate, in particular, on optical implementation as a means of achieving a simple, elegant, and practical implementation of a computer that is based on this new principle, specifically on the optical parametric oscillator that can achieve quantum neural networks at room temperature.This article introduces the concepts, technologies, and target applications making up this research field at PHI Labs.
The emerging field of Quantum Computing (QC) is attracting considerable research interest due to its potential. It is in fact believed that QC could revolutionize the way we approach complex problems by significantly reducing the time required to solve them. Although QC is still in its early stages of development, certain problems can already be addressed using quantum computers, offering a glimpse into its capabilities. The goal of the QuantumCLEF lab is to raise awareness of QC and to design, develop, and evaluate new QC algorithms aimed at solving challenges typically encountered in the implementation of Information Retrieval (IR) and Recommender Systems (RS). Furthermore, the lab provides a valuable opportunity to engage with QC technologies, which are often difficult to access. In this work, we present an overview of the second edition of QuantumCLEF, a lab focused on applying Quantum Annealing (QA), a specific QC paradigm, to three tasks: Feature Selection for IR and RS systems, Instance Selection for IR systems, and Clustering for IR systems. A total of 44 teams registered for the lab, with 5 teams successfully submitting their runs in accordance with the lab guidelines. Given the novelty of the topics, participants were provided with extensive examples and comprehensive materials to help them understand how QA works and how to program quantum annealers.