Ultrasonic delay time in typical optical glasses was measured between -20° and 120°C using superposition method at 5 MHz, which assured the precision of 1 in 10 4 . It was found out that the temperature coefficients of delay time of measured glasses lie in the range of ±50 ppm/°C, and shift from negative to positive as SiO 2 content decreases. The frequency dependence of acoustic loss was also measured using pulse echo method up to 130 MHz, and was found to be in the range of 0.01∼0.03 dB per unit wavelength.

10.1143/jjap.6.802

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Citations (3)

Applications of Surface Acoustic Wave Devices

OYOBUTURI (1976)

Takahiro Inamura Shokichiro Yoshikawa

Source

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Citations (1)

Temperature Dependence of Maximum DC Josephson Current through Grain Boundary Junctions in BaPb_0.75Bi_0.25O₃ Films

Japanese Journal of Applied Physics (1982)

Minoru Suzuki Toshiaki Murakami Youichi Enomoto Takahiro Inamura

Maximum DC Josephson current through grain boundary junctions in sputtered BaPb0.75Bi0.25O3 thin film was measured as a function of temperature. Experimental results show good agreement with the Ambegaokar-Baratoff theory at low temperatures, while in a definite temperature range just below Tc, they obey the (1-T/Tc)3/2 law, which reflects that grain boundary junctions change to proximity ones at high temperatures.

Atmospheric temperature range

10.1143/jjap.21.l437

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Citations (12)

Deep etching of epitaxial gallium nitride film by multiwavelength excitation process using F2 and KrF excimer lasers

Applied Physics A (2005)

Kotaro Obata Koji Sugioka Katsumi Midorikawa Takahiro Inamura Hiroshi Takai

Excimer

Laser Ablation

10.1007/s00339-005-3409-8

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Citations (9)

Thin Film Preparation of Superconducting Perovskite-Type Oxides by rf Sputtering

Japanese Journal of Applied Physics (1981)

Minoru Suzuki Youichi Enomoto Toshiaki Murakami Takahiro Inamura

Superconducting thin films of perovskite-type oxide of BaPb 1- x Bi x O 3 ( x =0.2, 0.25, 0.3, 0.4) and Ba 0.95 Sr 0.05 Pb 0.75 Bi 0.25 O 3 were prepared by rf sputtering with their superconducting transition onsets of about 8 K. The films tended to lack Pb and Bi and this tendency could be reduced by sputtering under sufficiently high oxygen partial pressure. The transition temperature becomes reduced in both cases of low ( x =0.2) and high ( x =0.4) Bi content. The strontium substitution aiming at sharp transitions was not so effective as in the bulk materials and resulted in high resistive thin films.

Resistive touchscreen

Partial pressure

Transition temperature

10.7567/jjaps.20s4.13

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Citations (12)

New Phenomena in Grain Boundary Josephson Junction Networks of BaPb_0.7Bi_0.3O₃ Films

Japanese Journal of Applied Physics (1982)

Youichi Enomoto Minoru Suzuki Toshiaki Murakami Takahiro Inamura

The grain boundaries of superconducting BaPb 0.7 Bi 0.3 O 3 (BPB) sputtered thin films work as Josephson junctions and also form two-dimensional junction arrays. Each film was shaped into a cross-pattern, with a gate and control lines, crossing each other perpendicularly. When the control current exceeds a certain critical value, the I – V curve of the gate behaves in two different ways: (1) With W g < W c (gate and control line widths), Josephson current for the gate line shifts by 2 n Δ / e ( n : integer); (2) With W g > W c , curves in voltage state are elongated through the V -axis into the opposite quadrant.

10.1143/jjap.21.l384

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Citations (12)

Observation of Grain Boundary Josephson Current in BaPb_0.7Bi_0.3O₃ Films

Japanese Journal of Applied Physics (1981)

Youichi Enomoto Minoru Suzuki Toshiaki Murakami Takashi Inukai Takahiro Inamura

The grain boundaries of superconducting BaPb0.7Bi0.3O3 sputtered thin films were found to work as tunnelling barriers and to result in the Josephson effect. The current-voltage characteristics of the films show large hysteresis curves and the Josephson critical current density is two orders of magnitude larger than those ever observed in granular superconducting films of other materials.

Hysteresis

10.1143/jjap.20.l661

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Citations (56)

Aging Effects of Li-Ti-O Superconducting Compounds

Japanese Journal of Applied Physics (1981)

Takashi Inukai Toshiaki Murakami Takahiro Inamura

Aging effects in hot-pressed Li-Ti-O superconductors were studied by measuring electrical resistivity. When samples are stored in dry air, the resistivity is quite stable, but it is not stable in wet air. Lithium carbonate formation was detected in the sample by X-ray diffraction, showing a resistivity increase. It is thought that this lithium carbonate was formed by a reaction between Li-Ti-O and water on the sample surface. This consideration is supported by the fact that high density samples are more stable than those of low density.

Lithium carbonate

10.1143/jjap.20.l681

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Citations (10)