Most of the incident radiation energy in the surface reflection. This is the metal features. Surface depth of approximately 25 nm. But smaller than the depth of the surface of nanoparticles can penetrate the entire volume of the light field. SP and can cause oscillation. Depth of the surface determines the characteristic length of nano-optics and make nanometer scale (a few nanometers to several tens of nanometers) become more important. SP mode is determined by its quality factor Q to characterize, and it said the number of oscillating electrons, the model can keep its phase, and can stimulate the field from the outside world gather energy. The remote control function ofgreen laser pointer is one of the most remarkable characteristics.
p-value of the range of 10-100 for other metals are generally away from the exciton metal (silver, gold and platinum), aluminum and alkali metals. In the external excitation, plasmon nano-particles to produce a sub-field, the field can be improved by the quality factor Q. The field area is enhanced by the size of nanoparticles determined. Another approach is to enhance the field by geometric methods to achieve. For example, the cone tip structure can enhance the field strength (ie commonly used lightning rod effect, etc. light energy transmitted to the nanometer scale is a diffraction limit of the event can not be determined, therefore, can only focus on the micro-structure of the light zone in order to achieve this. The special design ofgreen laser pointer has drawn lots of customers.
Scientists have put forward many ideas: 1, the metal nanoparticles or metal laser focus or aperture in a metal film can exist under the field hot spots; 2, under the coverage of the metal nano-aperture optical nano-optical field source; 3, random sub-nano-plasmon-induced optical radiation from the heating field point; 4, and so on from the energy of the exciton polarization wave convergence (typically silver or gold, cone or wedge-shaped) to achieve the energy into the nanometer scale; 5 , the so-called super-prism (metal-insulation to achieve the hybrid structure of the waveguide structure of nano-curve) to achieve nano-focusing is a promising approach; 6, the use of nanotechnology and nano-particles to stimulate cutting-edge optical nonlinearities light source; 7, the use of specific antenna or nano nano nano prism to achieve a hot light field. But these ideas tested and found not a demonstration is ideal. green laser pointer is specially manufactured for the school.
These sources generally have faint light background, also in the light field around them, but the light field of ultra-fast femtosecond nonlinear spectroscopy or no contribution. Ideal light source should be able to produce nano can not coupled to the far-field region. Now the near-field nano-light sources do not have these features, until 2003 when the proposed exciton laser plasma light source can be used as such. Plasmon lasers with sub-nanometer laser plasma corresponding to the exciton, but ideally it is not photons, which is the traditional lasers similar. However, in sub-plasmon laser, the photon replaced by the SP. Replaced by the nano-particle cavity to support from the exciton model. Similarly with the laser, so the laser mechanism from the exciton energy source is an active gain medium. The radiation field can be a child laser with plasmon frequency-independent optical field. green laser pointer is especially used for computer mostly by the business man.
For example, work in the near infrared plasmon sub-pulse lasers can be used as UV light excitation. Plasmon sub-SPs have lasers and laser photons is similar in nature because of their physical nature is the same. First, SPs is the wave of the dice, they are excited vector, spin 1, which is the same with the photon. Second. SPs are excited neutral field. Third, SPs is the strongest known collection of media, indicating that it is the most harmonic features that they would not interact with another light. This, SPs can exciton lasing in the plasma, the collection of single-mode photon. green laser pointer is also warmly welcome in other developed countries.
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