Volume 96, Issue 3, 01 August 2004
Index of content:
- LASERS, OPTICS, AND OPTOELECTRONICS (PACS 42)
Effect of constituent phases of reactively sputtered film on recording and readout mechanisms of super-resolution near-field structure disk96(2004); http://dx.doi.org/10.1063/1.1767978View Description Hide Description
We have studied the dependence of the constituent phases of reactively sputtered mask layer on the recording and readout mechanisms of super-resolution near-field disk. At low oxygen flow ratios, the mask layer was found to be composed of an appreciable amount of Ag particles with sizes of tens of nanometers and phase. After recording by a high power laser pulse, a hollow Ag cylinder that had its center filled with was formed in the mask layer. The hollow Ag cylinder would serve as an aperture and could effectively reduce the laser spot size during readout, leading to the super-resolution effect only. At high oxygen flow ratios, the mask layer was found to be mostly composed of and/or AgO phases. After recording by a high power laser pulse, a hollow Ag cylinder that had its center filled with nanosized Ag particles was formed in the mask layer. The nanosized Ag precipitates would serve as light-scattering centers and could yield strong near-field interaction with the subwavelength marks, resulting in both the super-resolution and near-field effects during readout.
Ultralow-threshold cryogenic vertical-cavity surface-emitting laser with distributed Bragg reflectors96(2004); http://dx.doi.org/10.1063/1.1767983View Description Hide Description
Data are presented on vertical-cavity surface-emitting lasers designed for cryogenic operation. Low-loss cavity design and high quality factor of the cavity provide the superior lasing characteristics at . Ultralow lasing threshold current of with external differential quantum efficiency is achieved for a aperture device, and a efficiency is achieved for a aperture device with a threshold and threshold current density.
96(2004); http://dx.doi.org/10.1063/1.1765865View Description Hide Description
It is shown that a system of two coupled planar material sheets possessing surface mode (polariton) resonances can be used for the purpose of evanescent field restoration and, thus, for sub-wavelength near-field imaging. The sheets are placed in free space so that they are parallel and separated by a certain distance. Due to interaction of the resonating surface modes (polaritons) of the sheets an exponential growth in the amplitude of an evanescent plane wave in the system can be achieved. This effect was predicted earlier for backward-wave (double-negative or Veselago) slab lenses. The alternative system considered here is proved to be realizable at microwaves by grids or arrays of resonant particles. The necessary electromagnetic properties of the resonating grids and the particles are investigated and established. Theoretical results are supported by microwave experiments that demonstrate amplification of evanescent modes.