Nippon Telegraph and Telephone Corporation

Hirokazu Takenouchi

Takashi Kurokawa

Katsunari Okamoto

Kazunori Naganuma

Tetsuyoshi Ishii

Chikara Amano

Kouta Tateno

Hiroyuki Tsuda

Yoshio Itoh

Yoshitaka Ohiso

Yoshitaka Kohama

Hiroyuki Suzuki

Yutaka Miyamoto

Hidehiko Takara

Takeshi Umeki

Hiroki Itoh

Akio Tokura

Masaki Asobe

Tatsushi Nakahara

Kouji Enbutsu

Hiroshi Yoshimura

Isao Tomita

Ryo Takahashi

The phase sensitive amplifier according to the present invention is a phase sensitive amplifier that uses the optical mixing using a nonlinear optical effect to amplify the signal light. The phase sensitive amplifier according to the present invention includes: the first second-order nonlinear optical element; and the second second-order nonlinear optical element. The first second-order nonlinear optical element causes the fundamental wave light to generate second harmonic light used as pump light and separates only the second harmonic light. The second second-order nonlinear optical element includes a multiplexer to multiplex the signal light with the second harmonic light and spectrally separates only the amplified signal light. The multiplexed signal light and second harmonic light are used subjected to parametric amplification.

Optical amplifier

A small size, low power consumption optical signal processing apparatus is implemented. An optical packet is split into two portions, one of which is used for an optical pulse generator to generate a single optical pulse or an optical pulse train with a period k times the bit period of the optical packet. The single pulse or the optical pulse train is used for an all-optical serial-to-parallel converter utilizing a surface-normal optical switch to convert a second portion of the optical packet into k parallel optical signals, which are then converted into k parallel electrical signals by a photo detector array. The k parallel electrical signals are supplied to an Si-based electronic circuit that implements high-speed optical signal processing. By utilizing the electronic circuit as a memory circuit or label recognition circuit, a buffer processing, address extraction and the like can be implemented.

Optical signal processing method and optical signal processing apparatus

An optical signal processing apparatus includes a first optical waveguide and a first slab waveguide configured to equally distribute an output light of the first optical waveguide. A first arrayed waveguide includes an aggregate of optical waveguides changing in optical length by a constant interval for dividing the output light. A second slab waveguide focuses the optical output of the first arrayed waveguide. A spatial filter receives incident light focused by the second slab waveguide and distributes the incident light on a straight line. The spatial filter also modulates the light into a desired amplitude according to the position on the straight line. The apparatus also includes a second arrayed waveguide and an aggregate of optical waveguides changing in optical length by a constant interval for applying light modulated by the spatial filter to the second arrayed waveguide. Structure is provided for converging the output light of said second arrayed waveguide to a single point. The resulting output light is then appiled to a second optical waveguide.

Optical signal processing apparatus and optical signal processing method

A vertical-cavity surface-emitting semiconductor laser has first and second semiconductor multi-layered films, an active layer, and third and fourth semiconductor multi-layered films which are piled up on a GaAs substrate in that order. Furthermore, the first film is formed by piling up Al.sub.x-1 Ga.sub.1-x1 As layers (0.ltoreq.x1.ltoreq.1) and Al.sub.x2 Ga.sub.1-x2 As layers (0.ltoreq.x2.ltoreq.1) one after the other by turns. The second film is formed by piling up In.sub.x3 Ga.sub.1-x3 As.sub.y3 P.sub.1-y3 layers (0.ltoreq.x3, y3.ltoreq.1) and In.sub.x4 Ga.sub.1-x4 As.sub.y4 P.sub.1-y4 layers (0.ltoreq.x4, y4.ltoreq.1) one after the other by turns. The active layer is provided as an In.sub.x5 Ga.sub.1-x5 As.sub.y5 P.sub.1-y5 layer (0.ltoreq.x5, y5.ltoreq.1). The third film is formed by piling up In.sub.x6 Ga.sub.1-x6 As.sub.y6 P.sub.1-y6 layers (0.ltoreq.x6, y6.ltoreq.1) and In.sub.x7 Ga.sub.1-x7 As.sub.y7 P.sub.1-y7 layers (0.ltoreq.x7, y7.ltoreq.1) one after the other by turns. The fourth film is formed by piling up Al.sub.x8 Ga.sub.1-x8 As layers (0.ltoreq.x8.ltoreq.1) and Al.sub.x9 Ga.sub.1-x9 As layers (0.ltoreq.x9.ltoreq.1) one after the other by turns. In each film, each layer has a thickness corresponding to a value obtained by dividing an emission wavelength by a refractive index and 4.

Vertical-cavity surface-emitting laser and method for manufacturing the

The present invention relates to an optical signal processing apparatus and optical signal processing method which enable generation, waveform shaping, waveform measurement, waveform recording, correlation processing, and the like of optical pulses of 1-10 ps. A basic construction of the optical signal processing apparatus includes an optical waveguide, a first structure for equally distributing output light of the optical waveguide, an optical waveguide comprising an aggregate of optical waveguides changing in optical length by a constant interval, a arrayed waveguide for dividing the output light, second structure for focusing optical output of the arrayed waveguide, and a mirror for receiving and reflecting incident light focused by the second structure. Or, the apparatus includes an optical waveguide, first structure for equally distributing output light of the optical waveguide, a arrayed waveguide comprising an aggregate of optical waveguides changing in optical length by a constant interval for dividing the output light, second structure for focusing optical output of the arrayed waveguide, and a spatial filter for receiving light focused by the second structure to distribute the incident light on a straight line and making desired amplitude or phase modulation of the light according to the position on the straight line and reflecting the light.

A vertical-cavity surface-emitting semiconductor laser has first and second semiconductor multi-layered films, an active layer, and third and fourth semiconductor multi-layered films which are piled up on a GaAs substrate in that order. Furthermore, the first film is formed by piling up Al.sub.x1 Ga.sub.1-x1 As layers (0.ltoreq.x1.ltoreq.1) and Al.sub.x2 Ga.sub.1-x2 As layers (0.ltoreq.x2.ltoreq.1) one after the other by turns. The second film is formed by piling up In.sub.x3 Ga.sub.1-x3 As.sub.y3 P.sub.1-y3 layers (0.ltoreq.x3, y3.ltoreq.1) and In.sub.x4 Ga.sub.1-x4 As.sub.y4 P.sub.1-y4 layers (0.ltoreq.x4, y4.ltoreq.1) one after the other by turns. The active layer is provided as an In.sub.x5 Ga.sub.1-x5 As.sub.y5 P.sub.1-y5 layer (0.ltoreq.x5, y5.ltoreq.1). The third film is formed by piling up In.sub.x6 Ga.sub.1-x6 AS.sub.y6 P.sub.1-y6 layers (0.ltoreq.x6, y6.ltoreq.1) and In.sub.x7 Ga.sub.1-x7 As.sub.y7 P.sub.1-y7 layers (0.ltoreq.x7, y7.ltoreq.1) one after the other by turns. The fourth film is formed by piling up Al.sub.x8 Ga.sub.1-x8 As layers (0.ltoreq.x8.ltoreq.1) and Al.sub.x9 Ga.sub.1-x9 As layers (0.ltoreq.x9.ltoreq.1) one after the other by turns. In each film, each layer has a thickness corresponding to a value obtained by dividing an emission wavelength by a refractive index and 4.

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Atsugi, Japan

Hirokazu Takenouchi