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American Journal of Engineering and Applied Sciences Review Quantum Technology: Advances and Trends 1Lidong Wang and 2Cheryl Ann Alexander 1Institute for Systems Engineering Research, Mississippi State University, Vicksburg, Mississippi, USA 2Institute for IT innovation and Smart Health, Vicksburg, Mississippi, USA Article history Abstract: Quantum science and quantum technology have become Received: 30-03-2020 significant areas that have the potential to bring up revolutions in various Revised: 23-04-2020 branches or applications including aeronautics and astronautics, military Accepted: 13-05-2020 and defense, meteorology, brain science, healthcare, advanced manufacturing, cybersecurity, artificial intelligence, etc. In this study, we Corresponding Author: Cheryl Ann Alexander present the advances and trends of quantum technology. Specifically, the Institute for IT innovation and advances and trends cover quantum computers and Quantum Processing Smart Health, Vicksburg, Units (QPUs), quantum computation and quantum machine learning, Mississippi, USA quantum network, Quantum Key Distribution (QKD), quantum Email: [email protected] teleportation and quantum satellites, quantum measurement and quantum sensing, and post-quantum blockchain and quantum blockchain. Some challenges are also introduced. Keywords: Quantum Computer, Quantum Machine Learning, Quantum Network, Quantum Key Distribution, Quantum Teleportation, Quantum Satellite, Quantum Blockchain Introduction information and the computation that is executed throughout a transaction (Humble, 2018). The Tokyo QKD metropolitan area network was There have been advances in developing quantum established in Japan in 2015 through intercontinental equipment, which has been indicated by the number of cooperation. A 650 km QKD network was established successful QKD demonstrations. However, many problems between Washington and Ohio in the USA in 2016; a still need to be fixed though achievements of QKD have plan of a 10000 km QKD backbone network was been showcased. Main features of QKD technology lie in: launched in the country. A quantum metropolitan area (1) Communication is generally fulfilled on a hop-by-hop network was estAablished in the UK in 2016 and a basis due to a main characteristic of the QKD network—no practical national network for QKD and an international available quantum router or quantum repeater in practice; QKD network was planned. The Phase I network with a (2) QKD links are at all times performed in a point-to-point total length of about 256 kilometers was established in manner, thus leading to a restricted distance and a key rate South Korea in 2016. The Beijing-Shanghai Trunk Line that is inversely proportional to the limited distance. of QKD was created in China in 2017 and applications in Furthermore, QKD links are possibly unavailable if the electric power, finance and government administration public channel is congested or there is not enough key were demonstrated (Liu et al., 2018). material (Shahid et al., 2020). The Personal Identifiable Information (PII) leak from Twin-field QKD was developed to obtain a remote big consumer databases, including social security numbers, key distribution with a maximum distance of secure financial status and additional private information have transmission. However, there were still some problems become a major concern and increased the interest in in the source part though the security of the twin-field reliable methods of sensitive information processing. A QKD was ensured in its detection part. The source of growing requirement of online applications in healthcare light had been regarded to be a very good coherent state and financial areas highlights worries about information though this assumption was not met in an actual QKD sharing and privacy. Quantum technology has the potential system, which led to secure problems in practice. A to handle the privacy worries or concerns using quantum protocol called Sending-or-Not-Sending (SNS) was put cryptographic methods such as super dense coding, forward for fixing the security problems. A condition quantum seals and QKD, which help protect information was discussed that the Photon Number Distribution during the information transmission. Progress in quantum (PND) of the source is unknown for the SNS protocol. It computing has offered some techniques of obscuring stored was demonstrated a security analysis is still valid for a © 2020 Lidong Wang and Cheryl Ann Alexander. This open access article is distributed under a Creative Commons Attribution (CC-BY) 3.0 license. Lidong Wang and Cheryl Ann Alexander / American Journal of Engineering and Applied Sciences 2020, 13 (2): 254.264 DOI: 10.3844/ajeassp.2020.254.264 source with an unknown PND. It was shown that the connected quantum computer in a trapped ion system and SNS protocol performance in the light source monitoring has demonstrated algorithms with successful rates above the enables to keep nearly unchanged (Gao et al., 2019). Bounded-error Quantum Polynomial (BQP) threshold. The Standard quantum field theory has been thought to Hidden Shift (HS) and Bernstein-Vazirani (BV) algorithms govern all the processes of human consciousness such as have been compiled into native gates and executed on the emotions, personality, beliefs, psychology, thoughts, etc. hardware. The trapped ion quantum computer has been The brain-based consciousness has been considered as a used to accomplish the quantum implementation of the HS dynamic self-awareness concept, constructed by the and BV algorithms (Wright et al., 2019). brain’s cortical neurons as a quantum information field A framework for hybrid quantum-classical that continuously receives information/energy from the algorithms was presented that uses a quantum computer brain, evaluates and processes the information and (substantially smaller compared with the problem size). initiates responses. External sensory information that is Given a randomly small ratio of the quantum computer modelled as quantized electromagnetic waves has been to the problem size, a polynomial speedup for classical regarded to feed cortical neurons and ultimately build the divide-and-conquer algorithms was achieved. A trade-off brain-based consciousness Hamiltonian. Any external between the problem size and the speedup can be information or energy, instantly reaching to the brain- achieved. A small quantum computer can considerably based consciousness Hamiltonian, has been considered speed up the solving process of a small-size problem. as a perturbation (Erol, 2019). Also, it enables to obtain a more modest speedup of a The main purpose of this paper is to deal with the larger instance (Ge and Dunjko, 2020). advances and trends of quantum technology. Some A quantum computer can offer substantial speedup in challenges of quantum technology will also be presented. machine learning. Algorithms that require quantum speedup The following is the arrangement of the rest of the paper: in runtime rely on an efficient Quantum Random Access section 2 presents quantum computers and QPUs; Memory (QRAM) (a critical component) in addition to a section 3 introduces quantum computation and quantum quantum computer. In a QRAM, the number of required machine learning; section 4 describes quantum network; quantum routing operations scales up exponentially with the section 5 introduces QKD; section 6 presents quantum number of qubits in the algorithms (Gao et al., 2018). teleportation and quantum satellites; section 7 describes Quantum memories are a cornerstone of quantum quantum measurement and quantum sensing; section 8 computers as well as a global-scale quantum Internet with deals with post-quantum blockchain and quantum high performances. Low retrieval efficiency is a main blockchain; and section 9 is the conclusion. problem of quantum memories. A High-Retrieval- Efficiency (HRE) quantum memory was defined for a near- Quantum Computers and Quantum term quantum device. A unit of the HRE quantum memory Processing Units was integrated with local unitary operations on its hardware level and utilized cutting-edge technologies in quantum Superconductors, quantum dots, ion traps, linear machine learning. It was proven the local unitary of the optics, donor systems, distributed and monolithic HRE quantum memory achieves an optimized and diamonds and topological quantum computing help to unsupervised readout procedure. It was shown that the develop quantum computers. The 4th-generation readout procedure of the HRE quantum memory was quantum computer utilizes the technology of topological accomplished without any information regarding an input quantum computing (also called anionic quantum quantum system or an unknown quantum operation of a computing) (Gyongyosi and Imre, 2019). Trapped quantum register. The retrieval efficiency of the HRE atomic ions provide one of primary physical platforms quantum memory and the output of the Signal-to-Noise for realizing a completely functional quantum computer, Ratio (SNR) was evaluated. The HRE quantum a programmable quantum computer prototype was memory is an especially convenient unit for a gate- displayed, and its performance was compared with that model quantum computer and the quantum Internet of a superconducting quantum computer with a similar (Gyongyosi and Imre, 2020). size. Among all of qubit technologies, trapped ion qubits IBM launched the IBM Q Experience, which made demonstrate the highest gate quality. Despite promises, universal quantum computers accessible
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