Zhu Bao-Hua

Study on the channel effect of deposition characteristics of neutral atoms in the laser standing wave field

Based on semiclassical theory, a model of the interaction between neutral atoms and the laser standing wave field has been established in this article. The trajectories and the deposition characteristics are analyzed with channel effect, and the full width at half maximum of nano-grating is 96.70, 0.532 and 12.16 nm when the divergence angle, spherical and chromatic aberration are discussed, respectively. The simulation results show that the contrast of the stripes decreases with the increasing divergence angle of the atomic beam. Also, the contrasts of the stripe are 85.2:1 and 5.33:1 when the divergence angles equal 0.1 and 0.3 mrad. Owing to the scission of the stripe, the quality of the deposition deteriorates with a divergence angle over 0.5 mrad.

The influence of divergence angle on the deposition of neutral chromium atoms using a laser standing wave

The characteristics of neutral chromium atoms in the standing wave field are discussed. Based on a semi-classical model, the motion equation of neutral atoms in the laser standing wave field is analyzed, and the trajectories of the atoms are obtained by simulations with the different divergence angles of the atomic beam. The simulation results show that the full width at half maximum (FWHM) of the stripe is 2.75 nm and the contrast is 38.5: 1 when the divergence angle equals 0 mrad, the FWHM is 24.1 nm and the contrast is 6.8:1 when the divergence angle equals 0.2 mrad and the FWHMs are 58.6 and 137.8 nm, and the contrasts are 3.3: 1 and 1.6: 1 when the divergence angles equal 0.5 and 1.0 mrad, respectively.

The analysis and research for the laser beam through turbulence atmosphere channel

In free space optical communication system, the characteristics of turbulence atmosphere are very important for this system. In this paper, the reason which conduce atmosphere turbulence is discussed, based on these analyse, three dimensional simulation of laser beam with different laser wavelength, different turbulence condition and different transmit distance are given, respectively. These simulation results are very important for free space optical communication.

Analysis of Nanometer Structure for Chromium Atoms in Gauss Standing Laser Wave

The equation of motion of two-level chromium atoms in Gauss standing laser wave is discussed and the distribution of chromium atoms is given under different transverse velocity conditions. The results show that the focusing position of atoms will be affected by the transverse velocity of atoms. Based on the four-order Runge-Kutta method, the locus of chromium atoms in Gauss standing laser wave is simulated. The three-dimensional characteristics of nanometer structures are stimulated under perfect and emanative conditions.

Simulation of Chromium Atom Deposition Pattern in a Gaussain Laser Standing Wave with Different Laser Power

One-dimensional deposition of a neutral chromium atomic beam focused by a near-resonant Gaussian standing-laser field is discussed by using a fourth-order Runge-Kutta type algorithm. The deposition pattern of neutral chromium atoms in a laser standing wave with different laser power is discussed and the simulation result shows that the full width at half maximum (FWHM) of a nanometer stripe is 115 nm and the contrast is 2.5:1 with laser power 3.93 mW; the FWHM is 0.8 nm and the contrast is 27:1 with laser power 16 mW, the optimal laser power; but with laser power increasing to 50 mW, the nanometer structure forms multi-crests and the quality worsens quickly with increasing laser power.