The dependence of the shift of an optical bistability hysteresis curve on the nonlinear phase shift induced by a controlling light is observed in a four-level atomic system of 87 Rb inside an optical ring cavity. In the process the intensity of the coupling beam keeps constant and the atomic system is operated at near conditions of coherent population trapping due to atomic coherence. The refra...

A 14.5 GHz ECRIS has been designed and fabricated at KAERI (Korea Atomic Energy Research Institute) to produce multi-charged ion beam (especially for C ion beam) for medical application. The magnet system has cupper conductor solenoid coils and a permanent magnet hexapole. A welded tube with aluminium and stainless steel is used for an ECR plasma chamber to improve the production of secondary e...

In this letter, we describe the on-demand dispensing of single liquid droplets with volumes down to a few attoliters and submicrometric spacing. This dispensing is achieved using a standard atomic force microscope probe, with a 200 nm aperture at the tip apex, opened by focused ion beam milling. The inside of the tip is used as reservoir for the liquid. This maskless dispensing, realized in amb...

A fundamental issue in ferroic systems (ferromagnetic and ferroelectric) is the scaling of the order parameter (magnetization or polarization) with size. Specifically, in ferroelectric thin films, deviations in the polarization can occur due to: (i) competition between thermal vibrations and the correlation energy (which aligns the dipoles); (ii) damage during fabrication. These deviations will...

The use of carbon nanotubes as tips in atomic force microscopy for a systematic study of dry etching pattern transfer in GaAs is described. The GaAs samples are patterned via electron beam lithography and then etched using magnetron reactive ion or chemically assisted ion beam processing. The technique allows diagnosis, in air, of etched features with scale sizes of ,100 nm. © 1998 American Ins...

In this study, the effects of dwell time on Ga focused ion beam machining at 30 keV for different milling currents were investigated. The surface topographies were analysed using atomic force microscopy (AFM) and the substrate structures were investigated by means of Raman spectroscopy. It has been observed that by increasing dwell time the total sputtering yield was increased even though the t...

The performance of atomic force microscopy cantilevers, as measured by the resonant frequency and spring constant, is directly dependent on the shape of the cantilever. Here we have improved the performance of conventional silicon nitride cantilevers by using focused ion beam milling to minimize the width of the cantilever legs. The resonant frequency in solution for any given spring constant i...