Hou Chun-Feng

Incoherently coupled screening-photovoltaic soliton families in biased photovoltaic photorefractive crystals

It is shown that the existence of incoherently coupled screening-photovoltaic soliton families is possible in biased photovoltaic photorefractive crystals under steady-state conditions. These screening-photovoltaic soliton families can be established provided the multiple incident beams have the same polarization and wavelength and are mutually incoherent. Such soliton families reduce to screening-photovoltaic soliton pairs when they contain only two components. Relevant examples are presented where the photovoltaic photorefractive crystal is of the lithium niobate type.

Bright-dark incoherently coupled photovoltaic soliton pair

The coupling between two mutually incoherent optical beams that propagate collinearly in open-circuit photovoltaic photorefractive media is investigated. It is shown that an incoherently coupled bright–dark spatial soliton pair can be formed due to photovoltaic effect. The physical properties of such a soliton pair are also discussed.

Grey spatial solitons due to two-photon photorefractive effect

This paper predicts that grey spatial solitons can exist in two-photon photorefractive materials. In steady state and under appropriate external bias conditions, it obtains the grey spatial soliton solutions of the optical wave evolution equation. The intensity profile, phase distribution, and transverse velocity of these grey solitons are discussed.

Characteristics of surface waves in anisotropic left-handed materials ∗

We report the coexistence of TE and TM surface modes in certain same frequency domain at the interface between one isotropic regular medium and another biaxially anistotropic left-handed medium. The conditions for the existence of TE and TM polarized surface waves in biaxially anisotropic left-handed materials are identified, respectively. The Poynting vector and the energy density associated with surface modes are calculated. Depending on the system parameters, either TE or TM surface modes can have the time averaged Poynting vector directed to or opposite to the mode phase velocity. It is seen that the characteristics of surface waves in biaxially anisotropic left-handed media are significantly different from that in isotropic left-handed media.

Energy levels and states of parabolic cylindrical lens shaped quantum dots

The parabolic cylindrical lens shaped quantum dot is investigated theoretically. The Schr?dinger equation for an electron confined in this structure is solved in the parabolic cylindrical coordinate system. The wavefunctions for the electron are presented in terms of confluent hypergeometric functions and the electron energy spectra are also obtained.

Grey－grey incoherently coupled spatial soliton pairs in guest－host photorefractive polymers

We show that incoherently coupled grey–grey spatial soliton pairs can be established in guest–host photorefractive polymers under steady-state conditions, provided that their carrier beams have the same polarization, wavelength and are mutually incoherent. The properties of these soliton pairs, such as their width and polarization, are discussed in detail.

Bound states of the Klein-Gordon equation with vector and scalar Wood-Saxon potentials

The S-wave Klein-Gordon equation with vector and scalar Wood-Saxon potentials is solved, and the energy levels are given through an equation.

Relativistic Electromagnetic Solitary Wave in a Cylindrical Magnetized Plasma

In the presence of an applied static and uniform magnetic field, a cylindrical Kadomtsev–Petviashivili equation is derived for a relativistic electromagnetic solitary wave propagating in collisionless plasma consisting electrons, positrons, and ions in the case of weak relativistic limit. This equation is solved in a stationary frame to obtain explicit expression for the velocity, amplitude and width of solitons. The amplitude of the solitary wave has a maximum value at a critical αc of the ratio of the ion equilibrium density to the electron one, and it increases as the applied magnetic field becomes larger.