We present experimental evidence of polarization storage by nonlinear orientational hole burning in films of poly(methylmethacrylate) containing disperse red one (DR1). The data are written by polarized nonlinear excitation of DR1 by a tightly focused Ti: Sapphire laser and read by polarized confocal laser scanning microscopy in the reflection mode. The bits that are imaged with a light polarization which is parallel to the excitation laser polarization reflect light ∼2.5 times more efficiently than those which are imaged with a light polarization which is perpendicular to it. This finding is consistent with orientational hole burning of chromophores by two-photon excitation.

We report critical roles that are played by laser system parameters in two-photon laser nanofabrication, which are not significant in rapid prototyping at larger scale, including: ͑i͒ polarization-induced lateral deshaping of volume elements, voxels, the primitive building block of micronanostructures, and ͑ii͒ lateral size reduction of voxels at low numerical aperture lens focusing due to thresholding effect. Also interesting is ͑iii͒ simultaneous recording of zeroth-and higher-order diffraction patterns, which was not hindered by the two-order light intensity difference by taking the advantage of the large dynamic exposure time range of general resins, a concept that is proposed in contrast to dynamic power range.

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Double differential thick target neutron yields from 5and 9 MeV deuteron incidence on aluminum and SUS304st ainless steel were measured at the Kyushu University Tandem Accelerator Laboratory. An aluminum, and a SUS 304 foil which were thick enough for a deuteron to stop in the foils were placed at the center of a vacuum chamber. AnNE213 liquid organic scintillator was employed to detect neutrons emitted from targets. To consider the contribution of scattered neutrons from the floor, we also measured neutron yields with an iron shadow bar located in front of the scintillator. Because incident deuteron beam was not pulsed and the Time-of-Flight method was not applied, the energy spectrum was derived from unfolding the light output spectrum using the FORIST code. The re sponse function of the detector was calculated with the SCINFUL-QMD code. The experimental results were compared with the calculation data of the TALYS and PHITS code, and it turned out that the calculation data does not reproduce the experimental ones satisfactorily.