We report on the design of <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\lambda/4$</tex> </formula> -shifted DFB laser that can provide high output efficiency as well stable single-mode operation. In particular, we investigate effects asymmetry in grating structure lasing characteristics Notation="TeX">$\lambda/4$</tex></formula> theoretically and experimentally. The steady-state mode-stability...

We present a ten-channel distributed feedback laser diode array (DFB-LDA) developed for the transmission of 100-Gb/s (10 × 10 Gb/s) signals separated by an 8 nm wavelength grid at center 1.55 μm. For fabrication this type array, selective area growth (SAG) technique, electron-beam lithography, and reverse-mesa ridge waveguide LD processing technique were adopted to offer tailored gain spectrum each channel, providing both accurate lasing-wavelength control excellent single-mode yield over...

We present a cost-effective 25-Gb/s electro-absorption modulator integrated laser (EML) transmitter optical sub-assembly (TOSA) using all-in-one flexible printed circuit board (FPCB) wiring and metal bench (MOB). For low cost high bandwidth TOSA, internal external wirings feed-through of the TOSA to transmit radio-frequency (RF) signal are configured FPCB. The FPCB is extended from an exterior package up EML chip inside through slit formed on rear sidewall die-bonded MOB. shows modulated...

We report a 1.5 μm and 10 Gb s−1 etched mesa buried heterostructure λ/4-shifted distributed feedback laser diode (DFB-LD) for the low-cost application of WDM–based datacenter networks. To reduce threshold current improve modulation bandwidth in conventional p-/n-/p-InP blocking structure, thin undoped-InP (u-InP) layer was inserted between side walls active region p-InP (i.e., u-/p-/n-/p-InP structure), containing structures form an mesa). From this work, it found that 300 long...

We report a novel structure that is capable of wide wavelength tuning in the distributed Bragg reflector laser diode (DBR-LD) with single grating mirror. This device's DBR section has two elements, plasma, and heater tunings, which are implemented simultaneously on top waveguide by using an in-between dielectric layer. For proposed structure, three-dimensional thermal simulation was conducted. The results showed temperature profile within highly affected position metal conductivity...

We propose and demonstrate a novel tunable external-cavity laser diode that simultaneously achieves rapid tuning rate wide range by electrical control. This contains new-type integrated diode, collimating lens, diffraction grating mirror. The consists of Fabry-Pe/spl acute/rot waveguide-type deflector, which can deflect the beam passing through waveguide. By control current in deflector region, maximum wavelength variation 8.6 nm sidemode suppression ratio >35 dB were obtained.

We present and demonstrate a simple cost-effective technique for improving the modulation bandwidth of electroabsorption-modulated laser (EML). This utilizes RF resonance caused by EML chip (i.e., junction capacitance) bonding wire (i.e, inductance). analyze effects lengths wires on frequency responses using an equivalent circuit model. To verify this analysis, we package lumped sub-mount measure its responses. The results show that, proposed technique, can increase from ~16 GHz to ~28 GHz.

We report a 1.3-µm and 10-Gbps tunable distributed Bragg reflector laser diode (DBR-LD) for the low-cost application of wavelength division multiplex based mobile front-haul network. The device consists gain, phase control, DBR sections, implemented using butt-coupling method through monolithic integration introduction an etched mesa planar buried hetero-structure in waveguide structure. From work, 560-µm long DBR-LD with 220-µm micro-heater section has threshold current 10 mA ± 1 tuning...

We present a multi-channel λ/4-shifted distributed feedback laser diode array (DFB-LDA) for the low-cost application of wavelength division multiplexing-based datacenter networks. The gain spectrum and lasing each channel are controlled by utilizing selective area growth E-beam lithography techniques, respectively. To reduce power consumption improve uniformity proposed array, planar-buried hetero-structure (PBH) is introduced region containing active current blocking structures etched in...

We report on the design for an electroabsorption-modulated laser (EML) that can provide a high immunity to optical signal reflected from its output facet without any fabrication complexity and performance compromise. In particular, we theoretically investigate effects of residual reflection static dynamic performances high-speed EMLs. For this analysis, accurate consistent time-domain transfer-matrix-based model is developed. Based model, perform steady-state large-signal analyses EML with...

We describe a hybrid integration module of 10 × 10-Gb/s distributed feedback laser diode array (DFB-LDA) and planar light-wave circuit-based arrayed waveguide grating (AWG). For fabrication the DFB-LDA, we adopted selective area growth technique to tailor channel gain properly, E-beam lithography accurately control lasing wavelength phase. implementation AWG, introduced 2%-Δ structure reduce coupling loss between AWG designed tapered parabolic waveguides at junctions free propagation regions...

Asymmetric multiple-quantum-well laser diodes with wide and flat gain spectra were designed, fabricated, analyzed. The active layer was composed of three 10-nm, one 8-nm, two 6-nm 0.5% compressive strained wells four 10-nm 5-nm 0.4% tensile barrier layer. Measured antireflection-coated ridge waveguide such quantum-well structures have shown that -1-dB spectral bandwidth can be as large 90 nm.

We have demonstrated a high-power widely tunable sampled grating distributed Bragg reflector (SGDBR) laser integrated monolithically with semiconductor optical amplifier (SOA) having lateral tapered waveguide, which is the first to emit fiber-coupled output power of more than 10 dBm using planar buried heterostructure (PBH). The facet reflectivity SOA waveguide and two-layer AR coating TiO2 SiO2 was lower 3 × 10−4 over wide bandwidth 85 nm. spectra 40 channels spaced by 50 GHz within tuning...

A widely tunable grating cavity laser based on the Rowland circle construction for a concave is proposed and demonstrated. The device implemented by employing multichannel array structure in Littman configuration fabricated integrating all elements an InP substrate. Only one channel turned at time, with coarse tuning realized selecting appropriate element fine controlling beam deflection provided dispersive element. An overall range of 50 nm sidemode suppression ratio more than 30 dB has...

A multiwavelength grating cavity laser is reported using a novel design for multichannel light source based on an etched diffraction grating. Following the design, compact eight-channel device capable of fine-tuning has been realized by monolithically integrating semiconductor optical amplifiers, various passive waveguides, and deeply grating, providing high butt-coupling efficiency, low waveguide losses. As result, sidemode suppression ratio in excess 45 dB over all channels was achieved.

A novel InGaAsP/InP buried-ridg waveguide laser diode structure is proposed and demonstrated for use as a single-mode laser. The lateral mode of the device can be controlled by adjusting composition thickness InGaAsP layer grown over active region. Stable operation without kinks or beam-steering achieved successfully with transverse in junction plane even ridge width 9 μm up to an injection current 500 mA.

A novel grating cavity tunable laser is proposed and experimentally demonstrated. It realized by monolithically integrating a semiconductor optical amplifier, dispersive element, phase-control section, an etched diffraction in single chip. Tuning operation based on electrically controlled beam deflection provided element phase matching section. With the electrical control, wavelength tuning of 8.5 nm with sidemode suppression ratio about 35 dB has been successfully achieved.

A widely tunable multi-channel grating cavity laser is proposed and experimentally demonstrated. The device implemented in Littman configuration with an echelle based on Rowland circle construction realized by monolithically integrating all elements InP substrate. Lasing wavelength selected turning amplifier the appropriate channel element array, it tuned controlling light deflection electrically. 6-channel exhibits a tuning range of about 50 nm side mode suppression ratio more than 30 dB....

InP-based planar waveguide 48-channel concave grating demultiplexers with a channel spacing of 0.8 nm (100 GHz) are described and demonstrated. Polarization insensitivity flattened spectral response successfully achieved by the introduction polarization compensator two-focus grating, respectively. The fabricated device shows polarization-dependent wavelength shift less than 20 pm −3 dB width about 0.55 (68.75 over all channels.

We report a tunable distributed Bragg reflector-laser diode (DBR-LD) integrated with an electro-absorption-modulator (EAM) at operating wavelength of 1.3 µm. This LD consists gain, phase control (PC), DBR, and EAM sections, realized by using butt-coupling technique in monolithically integrating the multiple quantum wells (MQWs) passive core applying etched-mesa buried hetero-structure (EMBH) to resonance cavity (i.e., gain DBR section) deep-ridge type section fabricating waveguide structure....

We present a 10-Gb/s L-band reflective electro-absorption modulator integrated with semiconductor optical amplifier (REAM-SOA) having improved transmission performance at very low input power of seed light. To decrease the light, absorption characteristics REAM are adjusted to reduce amplified spontaneous emission light returned into SOA, suppressing gain saturation effect SOA. At considerably -16 dBm, REAM-SOA exhibits penalty about 1.2 dB after 50-km SMF transmission. Over wide range from...

Abstract We report an electroabsorption modulator (EAM)‐integrated distributed Bragg reflector laser diode (DBR‐LD) capable of supporting a high data rate and wide wavelength tuning. The DBR‐LD contains two tuning elements, plasma heater tunings, both which are implemented in the DBR section, have blue‐shift red‐shift through current injection, respectively. light created from is intensity‐modulated EAM voltage, integrated monolithically with using butt–joint coupling method. fabricated chip...

We present a distributed Bragg reflector-laser diode (DBR-LD) monolithically integrated with an electroabsorption modulator (EAM) offering 100-Gb/s pulse amplitude modulation 4-level (PAM-4) signal per sub-channel under CWDM window of 1.29 μm. For the structure, DBR-LD and EAM were implemented using trenched waveguide in tuning sections for achieving energy-efficient wavelength-tuning deep ridge optimized structure PAM-4 operation, respectively. The fabricated chip shows threshold current...

Tunable external-cavity lasers with low power variation over a broad tuning range are demonstrated using asymmetric multiple quantum-wells wide and flat gain. For 2.8-μm-wide ridge waveguide laser of cavity length 380 μm, when used in grating external an antireflection coating on one facet diode chip, the less than -1 dB is obtained 80 nm. This extremely direct result spectrally

We report on a ridge waveguide laser diode with laterally tapered waveguides fabricated in single growing step using double patterning method. In this structure, nearly constant output power is obtained the change of lower width, and facet ratio 1.4 to 1.5 observed over current range. The asymmetric property also investigated.