China
Africa
Explore chapters and articles related to this topic
Secured Unmanned Aerial Vehicle-based Fog Computing Network
Published in Shashi Bhushan, Manoj Kumar, Pramod Kumar, Renjith V. Ravi, Anuj Kumar Singh, Holistic Approach to Quantum Cryptography in Cyber Security, 2023
Akshita Gupta, Sachin Kumar Gupta
Quantum cryptography is a very prominent area in which quantum mechanics principles are used to build a cryptosystem that is known to be the safest method. Quantum cryptography, also known as quantum encryption, uses the rules of quantum theory to symmetric encryption of messages so that no one except the receiver node can ever interpret them. Quantum cryptography is basically based on Heisenberg's uncertainty principle [20]. If in any case eavesdropper captures the keys during communication between UAV fog users and ground users, then quantum cryptography added the irregularities in the polarity of the photon and thus shows the violated communication. This helps to abort the ongoing communication and secure the infrastructure. The core of quantum cryptography arises from the fact that it incorporates the tiny individual particles, i.e., photons, which naturally occurs. These photon particles have great potential to reside concurrently in more than one state, and they alter their locations only when assessed [21]. Hua-Ying Liu and colleagues at Nanjing University in China developed the framework of quantum communications with UAVs. To establish a quantum communications channel between two ground stations nearby 1 km, a pair of UAVs were used. Multiple UAVs in pairs overcome the limitation of diffraction of photons [21,22].
Quantum Networks
Published in Jonathan P. Dowling, Schrödinger’s Web, 2020
The NPI document declared that the three pillars of the National Quantum Initiative are: quantum-limited and quantum-enhanced sensors of force fields and time,optical photonic quantum communication networks,quantum computers.All three of these topics fall under the rubric of quantum information science, which turned out to be the topic of the final version of the National Quantum Initiative Act. It may seem a bit odd that quantum sensors are considered part of quantum information science, but there is a reason for that. Way back in February of 1998, I gave the first public talk on quantum sensors, “From Quantum Computers to Quantum Gyroscopes,” at the NASA International Conference on Quantum Computing & Quantum Communications, in Palm Springs, California. I had been scheduled to give a talk on another topic, and my time slot was in the morning on Friday of the last day. I never gave my planned talk. Instead, after listening to the other presentations all week, I had one of my most profound ideas – a quantum sensor is a special-purpose quantum computer! A quantum computer is a machine that exploits unreality, uncertainty, and entanglement to solve mathematical problems much faster than a classical computer can.
Nanoelectronics and Mesoscopic Physics
Published in Vinod Kumar Khanna, Introductory Nanoelectronics, 2020
Macroscopic objects are subject to the laws of classical mechanics. Classical mechanics is not applicable to mesoscopic objects. Their theoretical treatment comes under the purview of quantum mechanics, also called wave mechanics, which is a fundamental theory in physics. Quantum mechanics is a branch of mechanics for mathematical formulation of motion and interaction of subatomic particles to describe nature at the smallest scales of energy levels of atoms and constituent particles. It incorporates: Quantization of energy, momentum, angular momentum, and other parameters of a bound system with constraint to allow discrete values only.Wave-particle duality of matter: All matter including electrons and electromagnetic fields behave as waves and particles.Uncertainty principle: Limit to the precision with which certain pairs of physical properties of a particle called complementary variables, e.g. position x and momentum p, energy E and time t, can be simultaneously measured.
The first iteration of Grover's algorithm using classical light with orbital angular momentum
Published in Journal of Modern Optics, 2018
Benjamin Perez-Garcia, Raul I. Hernandez-Aranda, Andrew Forbes, Thomas Konrad
Quantum mechanics offers an elegant way to accurately describe the physics of particles at the atomic and the subatomic level, which radically differs from the paradigm of classical mechanics to describe macroscopic particles. In fact, the physics of quantum particles governed by the superposition principle and showing interference phenomena seems closer related to classical fields obeying wave equations than to the behaviour of macroscopic mechanical objects. For instance, the Schrödinger equation describing the diffusion of the wave function of a free quantum particle on a plane resembles the wave equation of paraxial light diverging from an optical object. These similarities can be used to implement certain quantum mechanical applications with classical light instead. For example, classical optics schemes to realize quantum walks in one dimension (1, 2, 3) as well as in multiple dimensions (4) have been proposed and the real-time tomography of noisy single-photon channels by means of classical light was experimentally tested (5).
A perfect multi-hop teleportation scheme for transfer of five-qubit entangled states using intermediate nodes
Published in Journal of Modern Optics, 2018
Binayak S. Choudhury, Soumen Samanta
Teleportation protocols are for the purposes of transferring quantum states to a distant party. It was first advanced by Bennett et al. in 1993 [1] where arbitrary single qubit quantum states were teleported by use of entangled Bell states and with the support of classical communication. Several other teleportation protocols targeting two or more entangled states appeared in the literature in subsequent times. Some of the teleportation protocols are perfect teleportation protocols [2–9] by which it is meant that the state intended for transfer is sent with certainty and unit fidelity. There are also approximate teleportation protocols [10–12] in which the received state is an approximation of the state in the possession of the sender. Other teleportation protocols in which there exist certain chances of failures are called probabilistic teleportation processes [13–17]. Here our consideration is a perfect teleportation processes for the transfer of certain five-qubit entangled states. We describe some important protocols which transfer entangled states perfectly.
Role of CdSe quantum dots in the structure and antibacterial activity of chitosan/poly ɛ-caprolactone thin films
Published in Egyptian Journal of Basic and Applied Sciences, 2018
M.S. Meikhail, A.M. Abdelghany, W.M. Awad
Quantum dots (QDs) are spherical nano-sized crystals that may be formed of almost all semiconducting metals including CdSe, CdS, CdTe, PbS and ZnS while, alloys or any other metals may be used [16,17] . Cadmium selenide (CdSe) may be considered as an archetypal quantum dot with size range from 2 to 10 nm in diameter (10–50 atoms). Many types of quantum dot will emit light of specific frequencies if electricity or light is applied to them. These frequencies can be precisely tuned by changing the dot's size, [18,19] , giving rise to many applications. QDs were introduced to biological cell as alternative fluorescent probes in recent years. It uses in biological imaging, bio-sensing and intracellular detection and targeting, solar cells, quantum computing, transistors, LEDs and diode lasers [20]. Density function theory (DFT) is computational quantum mechanical method utilized as a part of physical science, material science to research the electronic structure (the ground state) of numerous body system, specifically particles, and atoms. It is a standout amongst the most well-known and effective quantum mechanical ways to deal with matter.