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In this report, Y-doped acoustic superlattice (ASL) lithium niobate (LN) crystal with linear taper of period was grown by the Czochralski method. The ferroelectric domain structure was revealed by optical photomicrograph. When an alternating electric field of frequency ranging from 680 MHz to 1100 MHz was applied, a ultrasonic wave with the same frequency was excited implying that a high-frequency bulk wave device with broad bandwidth could be fabricated.

Electro-optic (EO) effect of optical superlattice LiNbO3 (OSLLN), a single crystal with periodic ferroelectric domain structure was studied theoretically and experimentally. Because the electro-optic coefficient has different signs in different domains, the refractive index ellipsoid deforms periodically in the presence of an electric field applied along the Y-axis, which results in the coupling between the extraordinary wave and ordinary wave. Under specific conditions, the polarization of a light may be rotated to 90°, which means that the optical material could act as a precise spectral filter. The influence on the transmission spectrum of an OSLLN EO filter when there is another electric field along the Z-direction was also studied. It was demonstrated that the transmission peak could move with the electric field along the Z-axis if the duty cycle of the periodic structure is not 50%. Based on this effect, a tunable filter may be constructed.

The ionic-type phononic crystal (ITPC) is composed of two kinds of ferroelectric or piezoelectric media with a periodic superlattice structure. Through the piezoelectric effect, there is the coupling between the vibration of the superlattice and the electromagnetic (EM) wave that is similar to the coupling between the lattice vibration and the EM wave in ionic crystal. The ITPC thus exhibits interesting long wavelength optical properties, such as microwave absorption, dielectric abnormality and polariton excitation that exist originally in a crystal.

In this report, Y-doped lithium niobate (LN) crystal with periodic ferroelectric domain structure (PFDS) was grown by the current-induction technique. The distribution of dopant (Y) along the growth direction was measured by an electron-probe microscopic analyzer. The periodic variation of the dielectric constant in the crystal was revealed by the light diffraction. When a radio-frequency electric field was applied, a 340 MHz ultrasonic wave was excited in the sample by the crossed-field scheme, which implies that the LN with PFDS is suitable for constructing the high-frequency bulk-wave acoustic devices.

Electro-optic effect of periodically poled optical superlattice LiNb03 (OSLLN) was studied. A novel design of TE-TM mode converter based on PPLN waveguide is proposed. Conversion efficient is theoretically calculated, and the distribution of external electric field in the waveguide is analyzed. Full TE-TM conversion occurs when phase matching requirement is satisfied.

The electro-optic effect of periodically poled optical superlattice LiNbO3 (PPLN) was studied. Because of the periodic electro-optic (EO) coefficient, the reciprocal vector of the periodic structure can be used to compensate for the phase mismatch between the ordinary and extraordinary waves, which is similar to the nonlinear optical frequency conversion process. If the quasi-phase-matching condition is satisfied, polarization of a light propagated in PPLN can rotate linearly with the applied electric field, which shows that PPLN may be used as a precise spectral filter or an EO switch.

The influence of inhomogeneous interaction energy between deposited atoms and substrate atoms on island film growth is investigated by Monte Carlo simulation on a triangular lattice substrate. The Gaussian distribution is employed to describe the inhomogeneity of interaction energy. The results illustrate that the influence of inhomogeneous interaction energy on the growth of thin film is related to the degree of the inhomogeneity and the experimental conditions (such as substrate temperature).At medium temperature the inhomogeneity of interaction energy has notable influence on the island number and the island size. Increasing in temperature could counteract the influence of the inhomogeneity of interaction energy.

An acoustic superlattice LiNbO3 crystal with periodic ferroelectric domain structure was fabricated by introducing a periodic electric current through the solid–liquid interface during the crystal growing process. The domain morphology of an as-grown crystal was observed with a scanning electron microscope, and was found to be of good periodicity. A light diffraction experiment indicated that there was a periodic fluctuation of the dielectric constant along the crystal’s growing direction. Using the “crossed field” scheme, a 340 MHz ultrasonic was excited in the crystal, which means that the acoustic superlattice is suitable for constructing high-frequency bulk-wave acoustic devices.