8 research outputs found
Anyonic statistics with continuous variables
We describe a continuous-variable scheme for simulating the Kitaev lattice
model and for detecting statistics of abelian anyons. The corresponding quantum
optical implementation is solely based upon Gaussian resource states and
Gaussian operations, hence allowing for a highly efficient creation,
manipulation, and detection of anyons. This approach extends our understanding
of the control and application of anyons and it leads to the possibility for
experimental proof-of-principle demonstrations of anyonic statistics using
continuous-variable systems.Comment: 5 pages, 2 figures, appear in Phys. Rev.
Dependence of quantum correlations of twin beams on pump finesse of optical parametric oscillator
The dependence of quantum correlation of twin beams on the pump finesse of an
optical parametric oscillator is studied with a semi-classical analysis. It is
found that the phase-sum correlation of the output signal and idler beams from
an optical parametric oscillator operating above threshold depends on the
finesse of the pump field when the spurious pump phase noise generated inside
the optical cavity and the excess noise of the input pump field are involved in
the Langevin equations. The theoretical calculations can explain the previously
experimental results, quantitatively.Comment: 27 pages, 8 figure
Quantum Dense Coding Exploiting Bright EPR Beam
Highly efficient quantum dense coding for continuous variables has been
experimentally accomplished by means of exploiting bright EPR beam with
anticorrelation of amplitude quadratures and correlation of phase quadratures,
which is generated from a nondegenerate optical parametric amplifier operating
in the state of deamplification. Two bits of classical information are encoded
on two quadratures of a half of bright EPR beam at the sender Alice and
transmitted to the receiver Bob via one qubit of the shared quantum state after
encoding. The amplitude and phase signals are simultaneously decoded with the
other half of EPR beam by the direct measurement of the Bell-state at Bob. The
signal to noise ratios of the simultaneously measured amplitude and phase
signals are improved 5.4dB and 4.8dB with respect to that of the shot noise
limit respectively. A high degree of immunity to unauthorized eavesdropping of
the presented quantum communication scheme is experimentally demonstrated.Comment: 11 pages, 5 figure
Effect of silver nanoparticle addition on the structure and characteristics of radio-photoluminescence glass dosimeter
A series of silver-activated phosphate glass was prepared by melt quenching method. The effect of silver nanoparticle addition on the phosphate glass microstructure, composition and chemical characteristics was investigated using x-ray diffraction, fourier transform infrared and photoluminescence spectroscopy. Other physical property such as density was also evaluated. The density increased when the amount of silver ions were increased, due to the enhanced formation of non-bridging oxygen. In this study, we discuss the emission mechanism of two radio-photoluminescence peaks at 460 nm and 620 nm, where the electrons and holes produced by γ-irradiation a re-trapped by Ag+ ions to produce Ag0 and Ag2+ ions respectively, when the Ag+-doped phosphate glass is exposed to γ-ray. We proposed that an emission mechanism of 460 and 620 nm radio-photoluminescence peaks with these Ag2+ and Ag0 ions. Furthermore, a correlation between the investigated properties and glass composition is discussed
X-ray shielding behaviour of kaolin derived mullite-barites ceramic
Mullite-barite ceramic (MBC) is an emergent material for effective shielding of redundant ionizing radiation exposure. The composition dependent mechanical, thermal, and microstructure properties of MBC that makes MBC a high performing novel radiation shielding candidate remained unexplored. This paper examines the possibility of exploiting Malaysian kaolin (AKIM-35) and barite (BaSO4) derived ceramic (MBC) system for X-ray shielding operation. Using conventional pressing and sintering method six ceramic samples are prepared by mixing AKIM-35 with barite at varying contents (0, 10, 20, 30, 40 and 50 wt%). Synthesized pressed mixtures are calcined at 400 °C for 30 min and then sintered to 1300 °C for 120 min at a heating rate of 10 °C/min. Sintered samples are characterized via X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), lead equivalent (LE), uniformity and dose reduction analyses. XRD pattern of prepared ceramics revealed the presence of monoclinic barium alumino-silicate (BAS) and orthorhombic mullite as major shielding phases together with other minor phase of barite and hexagonal quartz (SiO2) structures. Furthermore, FESEM images of ceramics (between 0 and 30 wt%) displayed the existence of compacted monoclinic plate of BAS and acicular mullite morphology (ceramics at 40 and 50 wt%). Radiation tests displayed the capacity of ceramics (at 0 and 10 wt%) to shield the X-ray radiation emanated at tube potential range of 50–120 kV. The highest radiation attenuation is ascertained at 70 kV where the dose is reduced remarkably between 99.11% and 97.42%. Ceramics at 0 and 10 wt% demonstrated the highest lead (Pb) equivalent thickness (LE) of 0.44 mm and 0.34 mm, respectively. It is established that such MBC may contribute towards the development of shielding material against ionizing radiation in diagnostic radiology (X-ray) dose range