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Related papers: Positronium lifetime in polymers

200 papers

We present a time-resolved experimental study of the temperature effect on the coherence of traveling polariton condensates. The simultaneous detection of their emission both in real- and reciprocal-space allows us to fully monitor the…

Mesoscale and Nanoscale Physics · Physics 2020-04-23 E. Rozas , M. D. Martín , C. Tejedor , L. Viña , G. Deligeorgis , Z. Hatzopoulos , P. G. Savvidis

The positronium state in quartz is described by a linear superposition of two states: the first describing the free positron in the crystal and the second corresponding to a positronium Bloch wavefunction in the lattice. The condition for…

Materials Science · Physics 2009-11-18 B. Barbiellini , P. M. Platzman

Over the past two decades, open systems that are described by a non-Hermitian Hamiltonian have become a subject of intense research. These systems encompass classical wave systems with balanced gain and loss, semiclassical models with mode…

Quantum Physics · Physics 2021-10-27 Frantisek Ruzicka , Kaustubh S. Agarwal , Yogesh N. Joglekar

During particle collisions in the vicinity of the horizon of black holes, it is possible to achieve energies and temperatures corresponding to phase transitions in particle physics. It is shown that the sizes of the regions of the new phase…

General Relativity and Quantum Cosmology · Physics 2024-03-08 A. A. Grib , Yu. V. Pavlov

We present a novel type of soliton dubbed soft oscillons. In contrast with conventional oscillons the soft counterparts come in a continuum of unboundedly large sizes. They are peculiar also in that the oscillation frequency is set by their…

High Energy Physics - Theory · Physics 2025-07-23 Fabio van Dissel , Oriol Pujolàs

We present a study of thermodynamic properties of suspensions of charged colloids on the basis of linear Poisson-Boltzmann theory. We calculate the effective Hamiltonian of the colloids by integrating out the ionic degrees of freedom…

Soft Condensed Matter · Physics 2007-05-23 Bas Zoetekouw , Rene van Roij

We review the pair-production and decay of selectrons in $e^-e^-$ collisions and show how the standard model backgrounds can be virtually eliminated with polarized beams. The exceedingly simple analysis involved and the large sample of…

High Energy Physics - Phenomenology · Physics 2011-04-15 Frank Cuypers

We find a new effect for the behaviour of Von Neumann entropy. For this we derive the framework for describing Von Neumann entropy in non-Hermitian quantum systems and then apply it to a simple interacting PT symmetric bosonic system. We…

Quantum Physics · Physics 2019-08-01 Andreas Fring , Thomas Frith

Phonon lifetimes are a key component of quasiparticle theories of transport, yet first-principles lifetimes are rarely directly compared to inelastic neutron scattering (INS) results. Existing comparisons show discrepancies even at…

The short-time behavior of the survival probability of a system governed by a time-dependent non-Hermitian Hamiltonian is derived using to the second order perturbative approach. The resulting expression allows for the analysis of some…

Quantum Physics · Physics 2025-08-20 Benedetto Militello , Anna Napoli

We consider the effects of a massive, unstable neutrino on the evolution of large--scale structure and anisotropies in the cosmic microwave background. Comparison with large--scale structure data allows us to rule out a wide range of masses…

Astrophysics · Physics 2008-11-26 M. White , G. Gelmini , J. Silk

When neutrinos are produced from long lived particles the life-time of the source particle affects the flavour conversion probability formula. Due to this source dependence experiments (like LSND) which use muon decay neutrinos are two…

High Energy Physics - Phenomenology · Physics 2007-05-23 Subhendra Mohanty

In this study, we investigate the signatures of a non-commutative black hole solution. Initially, we calculate the thermodynamic properties of the system, including entropy, heat capacity, and Hawking radiation. For the latter quantity, we…

General Relativity and Quantum Cosmology · Physics 2024-08-29 A. A. Araújo Filho , J. R. Nascimento , A. Yu. Petrov , P. J. Porfírio , Ali Övgün

A new neutron lifetime experiment employing frozen Fomblin has produced a result in significant disagreement with previous experiments that used liquid Fomblin near room temperature. This new experiment is subject to very few corrections,…

Nuclear Experiment · Physics 2008-04-08 Steve K. Lamoreaux

We discuss the time evolution of physical finite dimensional systems which are modelled by non-hermitian Hamiltonians. We address both general non-hermitian Hamiltonians and pseudo-hermitian ones. We apply the theory of Krein Spaces to…

Mathematical Physics · Physics 2019-01-30 R. Ramirez , M. Reboiro

We are interested in the emission characteristics of an atom interacting with the polaritonic excitations of a semiconductor or insulator embedded in a one-mode cavity. Since polaritons inside of the cavity exhibit intrinsic squeezing, we…

Mesoscale and Nanoscale Physics · Physics 2018-07-18 Paolo Schwendimann , Antonio Quattropani

Inorganic scintillating crystals can be modelled as continua with microstructure. For rigid and isothermal crystals the evolution of charge carriers becomes in this way described by a reaction-diffusion-drift equation coupled with the…

Analysis of PDEs · Mathematics 2021-12-01 Fabrizio Davì

The lifetime of whispering gallery modes in a dielectric cavity with a metallic inclusion is shown to fluctuate by orders of magnitude when size and location of the inclusion are varied. We ascribe these fluctuations to tunneling…

chao-dyn · Physics 2009-10-31 Gregor Hackenbroich , Jens U. Noeckel

We investigate theoretically the quantum oscillator-like states recently observed experimentally in polariton condensates (Nat. Phys. 8, 190 (2012)). We consider a complex Gross-Pitaevskii type model which includes the effects of…

Quantum Gases · Physics 2016-02-17 Florian Pinsker , and Tristram J. Alexander

The persistence length of macromolecules is one of their basic characteristics, describing their intrinsic local stiffness. However, it is difficult to extract this length from physical properties of the polymers, different recipes may give…

Soft Condensed Matter · Physics 2013-03-12 Hsiao-Ping Hsu , Wolfgang Paul , Kurt Binder