Imaging of microwave-induced acoustic fields in LiNbO3 by high-performance Brillouin microscopy

in Journal of Physics : D Applied Physics (2005), 38(12), 2026-2030

High performance Brillouin microscopy (BM) has been used to characterize the spatial distribution of piezoelectrically induced acoustic fields excited at microwave frequencies in a LiNbO3 single crystal ... [more ▼]

High performance Brillouin microscopy (BM) has been used to characterize the spatial distribution of piezoelectrically induced acoustic fields excited at microwave frequencies in a LiNbO3 single crystal. It is demonstrated that under suitable conditions BM is able to detect microwave-induced bulk as well as surface acoustic waves. Brillouin spectroscopy is able to probe sound wave intensities of induced phonons, which are as small as those of thermal phonons. [less ▲]

Acoustic profilometry within polymers as performed by Brillouin microscopy

in Journal of Physics : D Applied Physics (2003), 36(21), 2738-2742

Using high performance Brillouin spectroscopy we present a new technique, which enables us to perform acoustic microscopy with a spatial resolution of about 1 μm. This technique, called Brillouin ... [more ▼]

Using high performance Brillouin spectroscopy we present a new technique, which enables us to perform acoustic microscopy with a spatial resolution of about 1 μm. This technique, called Brillouin microscopy, is tested on several bulk- and film-like polymer samples. [less ▲]

Nonlinear optical properties of Rb2ZnCl4 in the incommensurate and ferroelectric phases

in Physical Review. B, Condensed Matter and Materials Physics (1985), 32(3), 1649-1660

Nonlinear optical properties of Rb2ZnCl4 are measured for the incommensurate and ferroelectric phases by means of second-harmonic generation experiments. In the temperature range of the ferroelectric lock ... [more ▼]

Nonlinear optical properties of Rb2ZnCl4 are measured for the incommensurate and ferroelectric phases by means of second-harmonic generation experiments. In the temperature range of the ferroelectric lock-in phase, the nonlinear optical coefficients d33, d32, and d24 and the Miller coefficients are determined using the wedge technique and are shown to be proportional to the spontaneous polarization. In the incommensurate phase of Rb2ZnCl4, the order of magnitude of the second-harmonic intensity corresponding to nonlinear optical coefficients allowed by the local point-group symmetry is estimated to be at least 107 times smaller than the second-harmonic intensity generated in quartz and thus difficult to detect. Furthermore, it is shown that quasi-phase-matching of the fundamental and second-harmonic waves in the incommensurate phase is limited to a very small temperature range of TC [less ▲]

Evidence for low temperature phase transition in Rb2ZnCl4 from dielectric constant and birefringence measurements

in Solid State Communications (1981), 37(11), 883-888

Temperature dependences of the dielectric constants [epsilon]i and of the birefringences [Delta]ni for light propagation directions along all the three crystallographic axes (i = a, b, c) have been ... [more ▼]

Temperature dependences of the dielectric constants [epsilon]i and of the birefringences [Delta]ni for light propagation directions along all the three crystallographic axes (i = a, b, c) have been measured between 5 and 350 K. The optical measurements clearly reveal a new phase transition at TL = 75 K, below which the crystal structure is transformed from the ferroelectric Pna21 phase into an unknown low temperature phase, possibly the monoclinic space group P1121. Small peaks in the dielectric constants [epsilon]a and [epsilon]b have been observed at this transition temperature. [less ▲]