Accession Number : ADP008211

Title :   Field-Induced Refractive Index Change Dependence on Incident Light-Wavelength and Polarization to an InGaAs/InA1As Multi/Quantum Well,

Corporate Author : HITACHI LTD TOKYO (JAPAN) CENTRAL RESEARCH LAB

Personal Author(s) : Inoue, Hiroaki ; Sano, Hirohisa ; Nishimura, Shinji

Report Date : APR 1992

Pagination or Media Count : 2

Abstract : Field-induced refractive index change(Electro-refraction;ER) in multi-quantum well (MQW) structures arising from QCSE have become increasingly attractive for applications, especially in high speed, long-haul optical transmission systems. Because they have potential for low chirp, high speed modulation and for opto-electronic integration. Recently, highly efficient and small size MQW Mach-Zehnder(MZ) modulator had been reported. However, the reports on the modulation characteristics had concentrated into the modulation characteristics for TE-like mode of the waveguide structure. Their polarization and wavelength dependences have not been fully revealed yet. In this paper, we describe an ER dependence on incident light wavelengths and polarizations to an InGaAs/InAlAs MQW MZ modulator operating at 1.55 micrometer wavelength region the structure of our modulator is shown. The MQW was composed of 20 periods of InGaAs(60 angstrom)/InAlAs(60 angstrom), whose PL peak wavelength was 1.47 micrometer at room temperature. The absorption spectra showed the e-hh exciton absorption located at 1.47 micrometer and the e-lh at 1.40 micrometer, respectively. The device structures is the same as that of the previous report. The MZ interferometer consisted of 2 Y-branches and 2 phase modulation arms having the ridge waveguides structures. The both facets of the modulator were anti-reflection coated by SiNx. Examples of the intensity modulation characteristics of the modulators are shown with 1250 micrometer long arms.

Descriptors :   *REFRACTIVE INDEX, *FIBER OPTICS TRANSMISSION LINES, *ELECTROOPTICS, ABSORPTION SPECTRA, ELECTRONICS, EXCITONS, INTERFEROMETERS, MODULATION, MODULATORS, PHASE MODULATION, POLARIZATION, REFLECTION, ROOM TEMPERATURE, STRUCTURES, TEMPERATURE, VELOCITY, JAPAN, OPTICAL WAVEGUIDES.

Subject Categories : Electrooptical and Optoelectronic Devices
      Fiber Optics and Integrated Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE