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Two-colour holograms were recorded in a Tb-doped near-stoichiometric LiNbO3crystal by use of extraordinary 778 nm beams for writing and an ordinary 350 nm beam for gating. The dependences of two-colour recording sensitivity and the saturated diffraction efficiency on the intensities of the recording and gating beams are presented. The saturated diffraction efficiency increased with total writing intensity, and then reached a saturated value of 56% at an intensity of 20 W cm?2. The sensitivity increased linearly with gating intensity at low intensity, and then saturated with a value of 0.08 cm J?1at an intensity of 1.6 W cm?2. Fifty plane-wave holograms are recorded by the angle-multiplexing method and an M/# of 1.13 is obtained. [ABSTRACT FROM AUTHOR]

We have investigated nanoscale ferroelectric-domain engineering of a Sr 0.61 Ba 0.39 Nb 2 O 6 (SBN) single crystal using a scanning force microscope (SFM). A high-quality single crystal of SBN was grown by a newly developed double-crucible Stepanov method. The SBN crystal fixed on metal substrate was polished to a thickness of approximately 55 μm. Artificial nanoscale patterns of domain structures such as inverted-domain dot and inverted-domain mesh patterns were fabricated in the SBN samples, in which polarization directions of the domains were locally switched by scanning a SFM conductive cantilever along the sample surfaces under applied voltages. These results demonstrate that nanoscale domain patterning of ferroelectric single crystals, such as the SBN crystal, by using SFM is promising for creating novel functional devices. [ABSTRACT FROM AUTHOR]

We report the acoustic imaging frequency dynamics of ferroelectric domains by low-frequency acoustic probe microscopy based on the commercial atomic force microscopy It is found that ferroelectric domain could be firstly visualized at lower frequency down to 0.5 kHz by AFM-based acoustic microscopy The frequency-dependent acoustic signal revealed a strong acoustic response in the frequency range from 7kHz to 10kHz, and reached maximum at 8.1kHz. The acoustic contrast mechanism can be ascribed to the different elastic response of ferroelectric microstructures to local elastic stress fields, which is induced by the acoustic wave transmitting in the sample when the piezoelectric transducer is vibrating and exciting acoustic wave under ac electric fields due to normal piezoelectric effects. [ABSTRACT FROM AUTHOR]