Counterfactual quantum certificate authorization

We present a multi-partite protocol in a counterfactual paradigm. In counterfactual quantum cryptography, secure information is transmitted between two spatially separated parties even when there is no physical travel of particles transferring the information between them. We propose here a tripartite counterfactual quantum protocol for the task of certificate authorization. Here a trusted third party, Alice, authenticates an entity Bob (e.g., a bank) that a client Charlie wishes to securely transact with. The protocol is counterfactual with respect to either Bob or Charlie. We prove its security against a general incoherent attack, where Eve attacks single particles.Comment: 6 pages, 2 figures, close to the published versio

Nanoantenna-Microcavity Hybrids with Highly Cooperative Plasmonic-Photonic Coupling

Nanoantennas offer the ultimate spatial control over light by concentrating optical energy well below the diffraction limit, whereas their quality factor (Q) is constrained by large radiative and dissipative losses. Dielectric microcavities, on the other hand, are capable of generating a high Q-factor through an extended photon storage time but have a diffraction-limited optical mode volume. Here we bridge the two worlds, by studying an exemplary hybrid system integrating plasmonic gold nanorods acting as nanoantennas with an on-resonance dielectric photonic crystal (PC) slab acting as a low-loss microcavity and, more importantly, by synergistically combining their advantages to produce a much stronger local field enhancement than that of the separate entities. To achieve this synergy between the two polar opposite types of nanophotonic resonant elements, we show that it is crucial to coordinate both the dissipative loss of the nanoantenna and the Q-factor of the low-loss cavity. In comparison to the antenna-cavity coupling approach using a Fabry-Perot resonator, which has proved successful for resonant amplification of the antenna's local field intensity, we theoretically and experimentally show that coupling to a modest-Q PC guided resonance can produce a greater amplification by at least an order of magnitude. The synergistic nanoantenna-microcavity hybrid strategy opens new opportunities for further enhancing nanoscale light-matter interactions to benefit numerous areas such as nonlinear optics, nanolasers, plasmonic hot carrier technology, and surface-enhanced Raman and infrared absorption spectroscopies.Comment: Revised version after acceptanc

Thermodynamics of aluminum-barium alloys

The activity of barium in liquid Al-Ba alloys (XBa ≤ 0.261) at 1373 K has been determined using the Knudsen effusion-mass loss technique. At higher concentrations (XBa ≥ 0.38), the activity of barium has been determined by the pseudo-isopiestic technique. Activity of aluminum has been derived by Gibbs-Duhem integration. The concentration-concentration structure factor of Bhatia and Thornton[22] at zero wave vector has been computed from the thermodynamic data. The behavior of the mean-square thermal fluctuation in composition indicates a tendency for association in the liquid state. The associated solution model with Al5Ba4 as the predominant complex has been used for the description of the thermodynamic behavior of liquid Al-Ba alloys. Thermodynamic data for the intermetallic compounds in the Al-Ba system and the enthalpy of mixing in liquid alloys have been derived using the phase diagram and the Gibbs' energy of mixing of liquid alloys

A novel centralized supervisory with distributed control system-based microgrid

Supervisory Control and Data Acquisition is a popular control and monitoring scheme and is predominantly used in many industrial systems. Driven by the motivation of extending the usage of the SCADA systems for microgrid, a novel centralized Supervisory Control and Data Acquisition System with Distributed Control Systems is proposed and validated for the microgrid. Supervisory instructions are issued from the central control system, whereas the local controllers are used to implement the exclusive control schemes required for the various subsystems. A wired sensor network is used to monitor the various vital parameters and a Graphical User Interface (GUI) is used for monitoring the status of operation of the various subsystems along with their parametric values. The proposed system is simulated in the MATLAB SIMULINK environment. An experimental verification prototype has also been carried out where a PC (Personal Computer) with a Graphical User Interface developed in C# and a microcontroller is used to act as an interface between the distributed controllers in the plant and the master control PC

Transmission protocols in Cognitive Radio Mesh Networks

A Cognitive Radio (CR) is a radio that can adjust its transmission limit based on available spectrum in its operational surroundings. Cognitive Radio Network (CRN) is made up of both the licensed users and unlicensed users with CR enable and disabled radios. CR’S supports to access dynamic spectrum and supports secondary user to access underutilized spectrum efficiently, which was allocated to primary users. In CRN’S most of the research was done on spectrum allocation, spectrum sensing and spectrum sharing. In this literature, we present various Medium Access (MAC) protocols of CRN’S. This study would provide an excellent study of MAC strategies

G\"odel Incompleteness and the Black Hole Information Paradox

Semiclassical reasoning suggests that the process by which an object collapses into a black hole and then evaporates by emitting Hawking radiation may destroy information, a problem often referred to as the black hole information paradox. Further, there seems to be no unique prediction of where the information about the collapsing body is localized. We propose that the latter aspect of the paradox may be a manifestation of an inconsistent self-reference in the semiclassical theory of black hole evolution. This suggests the inadequacy of the semiclassical approach or, at worst, that standard quantum mechanics and general relavity are fundamentally incompatible. One option for the resolution for the paradox in the localization is to identify the G\"odel-like incompleteness that corresponds to an imposition of consistency, and introduce possibly new physics that supplies this incompleteness. Another option is to modify the theory in such a way as to prohibit self-reference. We discuss various possible scenarios to implement these options, including eternally collapsing objects, black hole remnants, black hole final states, and simple variants of semiclassical quantum gravity.Comment: 14 pages, 2 figures; revised according to journal requirement