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Hundred photon microwave ionization of Rydberg atoms in a static electric field  [PDF]
Giuliano Benenti,Giulio Casati,Dima L. Shepelyansky
Physics , 1997, DOI: 10.1103/PhysRevA.57.1987
Abstract: We present analytical and numerical results for the microwave excitation of nonhydrogenic atoms in a static electric field when up to 1000 photons are required to ionize an atom. For small microwave fields, dynamical localization in photon number leads to exponentially small ionization while above quantum delocalization border ionization goes in a diffusive way. For alkali atoms in a static field the ionization border is much lower than in hydrogen due to internal chaos.
Electric field induced nucleation: An alternative pathway to metallic hydrogen  [PDF]
M. Nardone,V. G. Karpov
Physics , 2011,
Abstract: Electric field induced nucleation is introduced as a possible mechanism to realize a metallic phase of hydrogen. Analytical expressions are derived for the nucleation probabilities of both thermal and quantum nucleation in terms of material parameters, temperature, and the applied field. Our results show that the insulator-metal transition can be driven by an electric field within a reasonable temperature range and at much lower pressures than the current paradigm of P > 400 GPa. Both static and oscillating fields are considered and practical implementations are discussed.
On the energy of electric field in hydrogen atom  [PDF]
Yuri Kornyushin
Physics , 2009,
Abstract: It is shown that hydrogen atom is a unique object in physics having negative energy of electric field, which is present in the atom. This refers also to some hydrogen-type atoms: hydrogen anti-atom, atom composed of proton and antiproton, and positronium.
The effect of parallel static and microwave electric fields on excited hydrogen atoms  [PDF]
D. Richards
Physics , 2004, DOI: 10.1088/1367-2630/7/1/138
Abstract: Motivated by recent experiments we analyse the classical dynamics of a hydrogen atom in parallel static and microwave electric fields. Using an appropriate representation and averaging approximations we show that resonant ionisation is controlled by a separatrix, and provide necessary conditions for a dynamical resonance to affect the ionisation probability. The position of the dynamical resonance is computed using a high-order perturbation series, and estimate its radius of convergence. We show that the position of the dynamical resonance does not coincide precisely with the ionisation maxima, and that the field switch-on time can dramatically affect the ionisation signal which, for long switch times, reflects the shape of an incipient homoclinic. Similarly, the resonance ionisation time can reflect the time-scale of the separatrix motion, which is therefore longer than conventional static field Stark ionisation. We explain why these effects should be observed in the quantum dynamics. PACs: 32.80.Rm, 33.40.+f, 34.10.+x, 05.45.Ac, 05.45.Mt
Semiclassical ionization dynamics of the hydrogen molecular ion in an electric field of arbitrary orientation  [PDF]
T. Bartsch,T. Uzer
Physics , 2004, DOI: 10.1088/0953-4075/38/2/018
Abstract: Quasi-static models of barrier suppression have played a major role in our understanding of the ionization of atoms and molecules in strong laser fields. Despite their success, in the case of diatomic molecules these studies have so far been restricted to fields aligned with the molecular axis. In this paper we investigate the locations and heights of the potential barriers in the hydrogen molecular ion in an electric field of arbitrary orientation. We find that the barriers undergo bifurcations as the external field strength and direction are varied. This phenomenon represents an unexpected level of intricacy even on this most elementary level of the dynamics. We describe the dynamics of tunnelling ionization through the barriers semiclassically and use our results to shed new light on the success of a recent theory of molecular tunnelling ionization as well as earlier theories that restrict the electric field to be aligned with the molecular axis.
On Nonexistence of Magnetic Monopoles: Deflection of Magnetic Needle in Static Electric Field of Electric Dipole Implies No Magnetic Field in the Universe  [PDF]
G. H. Jadhav
International Journal of Applied Physics and Mathematics , 2013, DOI: 10.7763/ijapm.2013.v3.187
Abstract: Motion of electrical charged particle in static curled electric field is studied. The electric field exerts asymmetric electric force which forces the particle to follow a curved path. Like in magnetic fields, the path is determined by instantaneous velocity of the particle and the field properties. This way, it shows a resemblance between the asymmetric electric force exerted in static curled electric field and the formal magnetic force exerted in static magnetic field. This resemblance permits to deflect a magnetic needle in static electric field, having non-zero curl, of an electric dipole. It implies the true nature of static magnetic force is static asymmetric electric force and the true nature of static magnetic field is static curled electric field. It provides answer to the question, why the magnetic monopoles are absent in the universe
Electric Field Enhanced Hydrogen Storage on BN Sheet  [PDF]
J. Zhou,Q. Wang,Q. Sun,P. Jena,X. S. Chen
Physics , 2009,
Abstract: Using density functional theory we show that an applied electric field substantially improves the hydrogen storage properties of a BN sheet by polarizing the hydrogen molecules as well as the substrate. The adsorption energy of a single H2 molecule in the presence of an electric field of 0.05 a.u. is 0.48 eV compared to 0.07 eV in its absence. When one layer of H2 molecules is adsorbed, the binding energy per H2 molecule increases from 0.03 eV in the field-free case to 0.14 eV/H2 in the presence of an electric field of 0.045 a.u. The corresponding gravimetric density of 7.5 wt % is consistent with the 6 wt % system target set by DOE for 2010. Once the applied electric field is removed, the stored H2 molecules can be easily released, thus making the storage reversible.
Motion of an electric dipole in a static electromagnetic field
Carl E. Mungan,Andrew Lasinski
Latin-American Journal of Physics Education , 2008,
Abstract: Expressions for the force and torque on a moving electric dipole in a magnetostatic field are combined with those due to an electrostatic field. By sending oriented molecular dipoles into a region of crossed magnetic and electric fields, the molecules are selectively rotated based on the direction and magnitude of their velocities. In principle this field configuration could be used to create a molecular isolator that only lets molecules through in one direction.
The hydrogen atom in an electric field: Closed-orbit theory with bifurcating orbits  [PDF]
T. Bartsch,J. Main,G. Wunner
Physics , 2002, DOI: 10.1088/0953-4075/36/6/312
Abstract: Closed-orbit theory provides a general approach to the semiclassical description of photo-absorption spectra of arbitrary atoms in external fields, the simplest of which is the hydrogen atom in an electric field. Yet, despite its apparent simplicity, a semiclassical quantization of this system by means of closed-orbit theory has not been achieved so far. It is the aim of this paper to close that gap. We first present a detailed analytic study of the closed classical orbits and their bifurcations. We then derive a simple form of the uniform semiclassical approximation for the bifurcations that is suitable for an inclusion into a closed-orbit summation. By means of a generalized version of the semiclassical quantization by harmonic inversion, we succeed in calculating high-quality semiclassical spectra for the hydrogen atom in an electric field.
Evidence For The Production Of Slow Antiprotonic Hydrogen In Vacuum  [PDF]
N. Zurlo,M. Amoretti,C. Amsler,G. Bonomi,C. Carraro,C. L. Cesar,M. Charlton,M. Doser,A. Fontana,R. Funakoshi,P. Genova,R. S. Hayano,L. V. Jorgensen,A. Kellerbauer,V. Lagomarsino,R. Landua,E. Lodi Rizzini,M. Macrì,N. Madsen,G. Manuzio,D. Mitchard,P. Montagna,L. G. Posada,H. Pruys,C. Regenfus,A. Rotondi,G. Testera,D. P. Van der Werf,A. Variola,L. Venturelli,Y. Yamazaki
Physics , 2007, DOI: 10.1103/PhysRevLett.97.153401
Abstract: We present evidence showing how antiprotonic hydrogen, the quasistable antiproton-proton (pbar-p) bound system, has been synthesized following the interaction of antiprotons with the hydrogen molecular ion (H2+) in a nested Penning trap environment. From a careful analysis of the spatial distributions of antiproton annihilation events, evidence is presented for antiprotonic hydrogen production with sub-eV kinetic energies in states around n=70, and with low angular momenta. The slow antiprotonic hydrogen may be studied using laser spectroscopic techniques.
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