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In this paper, we study some quantum properties of a superposition of displaced squeezed two-mode vacuum and single-photon states, such as the second-order correlation function, the Cauchy-Schwartz inequality, quadrature squeezing,…

Quantum Physics · Physics 2009-11-13 Faisal A. A. El-Orany , A-S. F. Obada , Zafer M. Asker , J. Perina

We study systematically the sensitivity of the photon structure function data on the gluon contents of the photon, by using the leading order Altarelli--Parisi (AP) equations. Charm quark contribution is studied in the quark parton model…

High Energy Physics - Phenomenology · Physics 2010-03-25 K. Hagiwara , T. Izubuchi , M. Tanaka , I. Watanabe

We calculate nuclear parton distribution functions (PDFs), using the constituent quark model. We find the bounded valon distributions in a nuclear to be related to free valon distributions in a nucleon. By using improved bounded valon…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Atashbar Tehrani , Ali N. Khorramian , A. Mirjalili

Some simple relations between unpolarized and polarized quark parton distributions have direct experimental consequences which will be presented here. In particular, we will see that it is possible to relate the deep inelastic structure…

High Energy Physics - Phenomenology · Physics 2009-10-28 Claude Bourrely , Jacques Soffer

Deep-inelastic scattering at low x and elastic vector meson production are considered on the basis of the off-shell extension of the s-channel unitarity. We discuss behavior of the structure function F_2(x,Q^2) at low x and the total…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. M. Troshin , N. E. Tyurin

At small-x, the structure function F_L(x,Q2) is driven by the gluon content of the nucleon target and consequently it can unravel the underlying QCD dynamics in that region. In this work, one studies its behavior on photon virtuality Q2 at…

High Energy Physics - Phenomenology · Physics 2009-11-11 Magno V. T. Machado

The first measurement of F_2,c^gamma is presented. At low x the measurement indicates a non-zero hadron-like component to F_2,c^gamma. At large x the measurement constitutes a test of perturbative QCD at next-to-leading order, with only m_c…

High Energy Physics - Experiment · Physics 2015-06-25 Richard Nisius

We consider a way to generate operational inequalities to test nonclassicality (or quantumness) of multimode (or multiparty) bosonic fields that unifies the derivation of many known inequalities and allows to propose new ones. The…

Quantum Physics · Physics 2010-07-23 Adam Miranowicz , Monika Bartkowiak , Xiaoguang Wang , Yu-xi Liu , Franco Nori

At variational level in the framework of dimensional reduced 'U_e(1)\times U_g(1)' electromagnetism it is considered an anyon Landau-Ginzburg Chern-Simons model for the fractional Hall effect. The collective gauge fields are due to…

High Energy Physics - Theory · Physics 2012-01-31 P. Castelo Ferreira

We analyze the three-mode correlation properties of the electromagnetic field in a optical parametric oscillator below threshold. We employ a perturbative expansion of the It\^o equations derived from the positive-P representation of the…

Quantum Physics · Physics 2011-07-15 K. Dechoum , W. S. Marques , A. Z. Khoury

The feasibility to generate correlated photon pairs at variable frequencies is investigated. For this purpose, we consider the interaction of an off-resonant laser field with a two-level system possessing broken inversion symmetry. We show…

Quantum Physics · Physics 2015-06-05 Fernando Oster , Christoph H Keitel , Mihai Macovei

A model is presented based on a dipole picture with a hard and a soft pomeron. It is assumed that large dipoles couple to the soft pomeron and small dipoels couple to the hard pomeron. Most of the parameters of the model are predetermined…

High Energy Physics - Phenomenology · Physics 2007-05-23 A Donnachie

We show that the first moment of the spin-dependent structure function $g_1^{\gamma}(x,Q^2)$ of a real photon vanishes independent of the momentum transfer $Q^2$ it is probed with. This result is non-perturbative: it holds to all orders in…

High Energy Physics - Phenomenology · Physics 2009-09-11 Steven D. Bass , Stanley J. Brodsky , Ivan Schmidt

We analyze virtual Compton scattering off the nucleon at low energies in a covariant, model-independent formalism. We define a set of invariant functions which, once the irregular nucleon pole terms have been subtracted in a gauge-invariant…

Nuclear Theory · Physics 2008-11-26 D. Drechsel , G. Knoechlein , A. Yu. Korchin , A. Metz , S. Scherer

In this paper, we have proposed the spinor wave equation of free and non-free photon. On this basis, we given the spin operators and spin wave functions of photon, and calculated the wave function of photon in vacuum and medium. In…

Optics · Physics 2019-02-19 Xiang-Yao Wu , Ben-Shan Wu , Qing Pan , Xiao-Jing Liu , Ji-Ping Liu , Xiao-Ru Zhang , Ji Ma

High-dimensional quantum entanglement in photons offers notable technological advancements over traditional qubit-based systems, including increased information density and enhanced security. However, such high-dimensional states are…

Quantum Physics · Physics 2025-02-13 Kiran Bajar , Rounak Chatterjee , Vikas S. Bhat , Sushil Mujumdar

We implement the direct sampling of negative phase-space functions via unbalanced homodyne measurement using click-counting detectors. The negativities significantly certify nonclassical light in the high-loss regime using a small number of…

Quantum Physics · Physics 2018-02-14 M. Bohmann , J. Tiedau , T. Bartley , J. Sperling , C. Silberhorn , W. Vogel

We review the different approaches used to treat the photon structure function. We suggest that despite some uncertainties it should remain sensitive to $\Lambda .$

High Energy Physics - Phenomenology · Physics 2008-02-03 L. Marleau

The diphoton channel at lepton colliders, $e^+e^- (\mu^+\mu^-) \to \gamma \gamma$, has a remarkable feature that the leading new physics contribution comes only from dimension-eight operators. This contribution is subject to a set of…

High Energy Physics - Phenomenology · Physics 2022-07-06 Jiayin Gu , Lian-Tao Wang , Cen Zhang

The light force on particles trapped in the field of a high-Q cavity mode depends on the quantum state of field and particle. Different photon numbers generate different optical potentials anddifferent motional states induce different field…

Quantum Physics · Physics 2009-04-17 András Vukics , Wolfgang Niedenzu , Helmut Ritsch