The vectorial structure of cosine-Gaussian beams (cGBs) is investigated in the far field regime based on the vector plane wave spectrum and the method of stationary phase. The energy flux densities of TE or TM term an...The vectorial structure of cosine-Gaussian beams (cGBs) is investigated in the far field regime based on the vector plane wave spectrum and the method of stationary phase. The energy flux densities of TE or TM term and the ratio of the energy flux of TE or TM term in the whole beam are demonstrated. It is found that the spot configurations of the energy flux densities associated with the TE and TM terms depend on the polarization angle and the beam parameter of the incident cGB. And the far field may be entirely transverse magnetic or transverse electric under appropriate polarization angle and beam parameter.展开更多
The focusing properties of azimuthally polarized hyperbolic-cosine-Gaussian (ChG) beam are investigated theoretically by vector diffraction theory. Results show that the intensity distribution in focal region of azimu...The focusing properties of azimuthally polarized hyperbolic-cosine-Gaussian (ChG) beam are investigated theoretically by vector diffraction theory. Results show that the intensity distribution in focal region of azimuthally polarized ChG beam can be altered considerably by decentered parameters, and some novel focal patterns may occur for certain case. On increasing decentered parameters, ring shape of focal pattern can evolve into four-peak focal pattern, and azimuthal field component affects focal pattern more significantly than radial field component. Optical gradient force is also calculated to show that the focusing properties may be used in optical tweezers technique.展开更多
This work reveals an exploration of self-focusing of Hermite-cosine-Gaussian laser beam in a collisionless plasma under relativistic nonlinearity. Self-focusing along with self-trapping of Hermite-cosine-Gaussian lase...This work reveals an exploration of self-focusing of Hermite-cosine-Gaussian laser beam in a collisionless plasma under relativistic nonlinearity. Self-focusing along with self-trapping of Hermite-cosine-Gaussian laser beam are analyzed for different values of laser intensity, plasma density, and decentered parameters. Mathematical analysis displays that these parameters play a major role in achieving the stronger and earlier self-focusing. Further, a comparative study between self-focusing of Hermite-cosine-Gaussian laser beam with and without exponential density ramp profile is introduced. Plasma density transition with exponential profile is found to be more effective in order to have stronger self-focusing. The present analysis may lead to very useful applications in the field of efficient harmonic generation, laser driven fusion etc.展开更多
文摘The vectorial structure of cosine-Gaussian beams (cGBs) is investigated in the far field regime based on the vector plane wave spectrum and the method of stationary phase. The energy flux densities of TE or TM term and the ratio of the energy flux of TE or TM term in the whole beam are demonstrated. It is found that the spot configurations of the energy flux densities associated with the TE and TM terms depend on the polarization angle and the beam parameter of the incident cGB. And the far field may be entirely transverse magnetic or transverse electric under appropriate polarization angle and beam parameter.
文摘The focusing properties of azimuthally polarized hyperbolic-cosine-Gaussian (ChG) beam are investigated theoretically by vector diffraction theory. Results show that the intensity distribution in focal region of azimuthally polarized ChG beam can be altered considerably by decentered parameters, and some novel focal patterns may occur for certain case. On increasing decentered parameters, ring shape of focal pattern can evolve into four-peak focal pattern, and azimuthal field component affects focal pattern more significantly than radial field component. Optical gradient force is also calculated to show that the focusing properties may be used in optical tweezers technique.
文摘This work reveals an exploration of self-focusing of Hermite-cosine-Gaussian laser beam in a collisionless plasma under relativistic nonlinearity. Self-focusing along with self-trapping of Hermite-cosine-Gaussian laser beam are analyzed for different values of laser intensity, plasma density, and decentered parameters. Mathematical analysis displays that these parameters play a major role in achieving the stronger and earlier self-focusing. Further, a comparative study between self-focusing of Hermite-cosine-Gaussian laser beam with and without exponential density ramp profile is introduced. Plasma density transition with exponential profile is found to be more effective in order to have stronger self-focusing. The present analysis may lead to very useful applications in the field of efficient harmonic generation, laser driven fusion etc.
