A 10 Gbit/s OEIC photoreceiver using InP/InGaAs heterojunction bipolar transistors

Metal organic molecular beam epitaxy (MOMBE) was successfully used for the first time to realise a high speed monolithic photoreceiver. Incorporating an InGaAs pin photodetector followed by a transimpedance preamplifier circuit implemented with InP/InGaAs heterojunction bipolar transistors (HBTs), the OEIC photoreceiver had a bandwidth of 6 GHz and a midband transimpedance of 350 Omega . In a system experiment performed at 10 Gbit/s, the receiver exhibited a sensitivity of -15.5 dBm for a bit error rate of 10/sup -9/ at a wavelength of 1.53 mu m. This is the first demonstration of operation of a long wavelength OEIC photoreceiver at this speed.<>     

8-Gbit/s transmission experiment over 68 km of optical fiber using a Ti:LiNbO3external modulator

We describe the performance of an experimental 1.5-μm lightwave transmission system operating at 8 Gbit/s over 68.3 km of single-mode fiber. The dispersion penalty is limited to 1 dB through the use of external modulation and is attributable to the intrinsic information bandwidth.     

A transimpedance APD optical receiver operating at 10 Gb/s

The authors report an optical receiver which uses a separate-absorption-and-multiplication avalanche photodiode (SAM-APD) to achieve high sensitivity at a bit rate of 10 Gb/s. A transimpedance front end incorporating HEMT devices is used for high bandwidth and low noise. The sensitivity (bit-error rate of 10^-9) is -28.7 dBm for a return-to-zero signal, and -27.0 dBm for a nonreturn-to-zero signal     

Coherent lightwave transmission at 2 Gbit/s over 170 km of optical fibre using phase modulation

We report coherent lightwave transmission at a data rate of 2Gbit/s over 170 km of optical fibre. Phase modulation is employed, and a bit error rate lower than 10-9 is achieved. The receiver sensitivity of ?39.0 dBm 10-9 BER) is an improvement of 2.4 dB over the best previously published direct-detection result for non-return-to-zero transmission.     

Dispersion-tolerant 10-gb/s duobinary system employing heterodyne detection and MLSE

We experimentally demonstrate a 10.7-Gb/s duobinary transmission system operating over a chromatic-dispersion range of /spl sim/12 000 ps/nm. Heterodyne detection and maximum-likelihood sequence estimation are employed to achieve this result.     

Analysis of poly(chlorophenyl methacrylates) by ultraviolet spectroscopy

Summary A number of copolymers of methyl methacrylate and chlorophenyl methacrylates of different structure was prepared and analyzed by ultraviolet spectroscopy. It was found that the copolymer composition can be determined using a calibration curve based on mixtures of the appropriate homopolymers. The U. V. spectroscopical results are in good agreement with the chlorine analysis.     

Monolithic demodulator for 40-gb/s DQPSK using a star coupler

A novel device that demodulates both quadratures of the optical differential quadrature phase-shift keying (DQPSK) format in a single interferometer by using a 4 /spl times/ 4 star coupler was demonstrated. Simultaneous measurements of both DQPSK quadratures at 42.7 Gb/s are also presented.     

One-third terabit/s transmission through 150 km ofdispersion-managed fiber

340 Gb/s (seventeen 20-Gb/s 2³¹-1 PRBS NRZ channels) were transmitted through 150 km of fiber with 50 km amplifier spacing. Chromatic dispersion penalties and four-photon mixing effects were minimized by dispersion management     

25.6-Tb/s WDM Transmission of Polarization-Multiplexed RZ-DQPSK Signals

We demonstrate record 25.6-Tb/s transmission over 240 km using 160 WDM channels on a 50-GHz grid in the C+L bands. Each channel contains two polarization-multiplexed 85.4-Gb/s RZ-DQPSK signals, yielding a spectral efficiency of 3.2b/s/Hz in each band.     

Strongly enhanced molecular fluorescence inside a nanoscale waveguide gap

We experimentally demonstrate dramatically enhanced light-matter interaction for molecules placed inside the nanometer scale gap of a plasmonic waveguide. We observe spontaneous emission rate enhancements of up to about 60 times due to strong optical localization in two dimensions. This rate enhancement is a nonresonant nature of the plasmonic waveguide under study overcoming the fundamental bandwidth limitation of conventional devices. Moreover, we show that about 85% of molecular emission couples into the waveguide highlighting the dominance of the nanoscale optical mode in competing with quenching processes. Such optics at molecular length scales paves the way toward integrated on-chip photon source, rapid transfer of quantum information, and efficient light extraction for solid-state-lighting devices.