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Under suitable conditions quantum eigenfunctions for mixed systems localize neither on the regular nor on chaotic components in phase space. Such exotic quantum states are called amphibious states, and the flooding of wave functions from regular to chaotic regions, or in the opposite way, are predicted to occur when the eigenstates become amphibious. The emergence of such new states has so far been verified in rather artificial model systems. Here we explore how generically the flooding of wave functions takes place and whether it is an observable phenomenon even in laboratory experiments such as atomic matter-wave systems. Since the flooding occurs as a result of the strong correlation between different types of quantum localization, dynamical tunneling and dynamical localization, there are several competing factors, some of them accelerate but other do not. We study a quasi-periodic kicked rotor with generic phase space to search optimal situations to realize the flooding phenomenon and discuss the compatibility of competing factors between different types of quantum localization. [ABSTRACT FROM AUTHOR]

We employ manipulated ultrafast laser pulses to realize microprocessing with high-performance. Efficient microwelding of glass substrates by irradiation by a double-pulse train of ultrafast laser pulses is demonstrated. The bonding strength of two photostructurable glass substrates welded by double-pulse irradiation was evaluated to be 22.9 MPa, which is approximately 22% greater than that of a sample prepared by conventional irradiation by a single pulse train. Additionally, the fabrication of hollow microfluidic channels with a circular cross-sectional shape embedded in fused silica is realized by spatiotemporally focusing the ultrafast laser beam. We show both theoretically and experimentally that the spatiotemporal focusing of ultrafast laser beam allows for the creation of a three-dimensionally symmetric spherical peak intensity distribution at the focal spot. [ABSTRACT FROM AUTHOR]

We demonstrate to fabricate microfluidic chips integrated with some functional elements such as optical attenuators and optical waveguides by femtosecond (fs) laser direct writing for mechanism study of gliding movement of Phormidium to a seedling root. Femtosecond laser irradiation followed by annealing and wet etching in dilute hydrofluoric (HF) acid solution resulted in formation of three-dimensional (3D) hollow microstructures embedded in a photosensitive glass. The embedded microfludic structures enabled us to easily and efficiently observe Phormidium gliding to the seedling root, which accelerates growth of the vegetable seedling. In addition, integration of optical attenuators and optical waveguides into the microfluidic structures in the microchip clarified the mechanism of the gliding movement of Phormidium. Such microchips, referred to as nanoaquariums, realized the highly efficient and functional observation and analysis of various microorganisms. [ABSTRACT FROM AUTHOR]