Multiwavelength DFB Laser Array Research Articles

Over 100 mW O-Band Multi-Wavelength DFB Laser Array for Optical I/O Technology

Over 100 mW O-Band Multi-Wavelength DFB Laser Array for Optical I/O Technology

Photonic convolution accelerator based on a hybrid integrated multi-wavelength laser array by photonic wire bonding for real-time image classification.

We propose and experimentally demonstrate a compact and efficient photonic convolution accelerator based on a hybrid integrated multi-wavelength DFB laser array by photonic wire bonding. The photonic convolution accelerator operates at 60.12 GOPS for one 3 × 3 kernel with a convolution window vertical sliding stride of 1 and generates 500 images of real-time image classification. Furthermore, real-time image classification on the MNIST database of handwritten digits with a prediction accuracy of 93.86% is achieved. This work provides a novel, to the best of our knowledge, compact hybrid integration platform to realize the optical convolutional neural networks.

ICP刻蚀优化及在多波长分布反馈式激光器阵列中的应用

ICP刻蚀优化及在多波长分布反馈式激光器阵列中的应用

Improved Single-Mode Property of DFB Semiconductor Laser Based on Sampling Technique Using Chirp Compensation

A DFB semiconductor laser with a bent waveguide and an equivalent chirp compensation based on the sampled grating technique is proposed to improve the single longitudinal mode (SLM) performance for the first time. In such a structure, the bent waveguide is used to form the basically chirped grating so that the zeroth-order resonance is greatly suppressed. However, for the $-$ first-order resonance, the equivalent chirp by designing the sampling pattern is used to compensate the chirp in the $-$ first subgrating caused by bent waveguide. As a result, the $-$ first-order resonance is enhanced, whereas the zeroth resonance is well suppressed. Since the wavelength spacing between the zeroth and $-$ first subgrating can be reduced by adopting this method, the sampling period can be increased. Therefore, the corresponding line in photomask can be enlarged as well to ease the fabrication, and the lasing wavelength accuracy can be further improved according to the theoretical analysis. Because the lasing wavelength can be controlled by changing the sampling period, the performances of the multiwavelength DFB laser array can also be improved using this method.

1.3-μm multi-wavelength DFB laser array fabricated by mocvd selective area growth

We report the fabrication of multi-wavelength DFB laser arrays operating around 1.3μm using a novel MOCVD based selective area growth approach. We show that the DFB laser wavelength can be precisely tuned by adjusting key design parameters including the oxide mask strip width and separation. Stable-single-mode DFB laser array operations are demonstrated with side mode suppression ratio >35dB and the wavelength span of DFB laser array can arrive at 13.9nm through optimizing the design parameters. Our process represents a simple and cost effective solution for applications requiring multi-wavelength laser sources covering a wide wavelength span, such as silicon photonic light sources in next generation 100G Gigabit Ethernet optical systems.

Study of the Multiwavelength DFB Semiconductor Laser Array Based on the Reconstruction-Equivalent-Chirp Technique

A detailed theoretical analysis of the lasing wavelength precision of the DFB laser array based on a reconstruction-equivalent-chirp (REC) technique is presented. Experimental results of the eight-wavelength DFB laser array with equivalent π phase shift (π-EPS) and four-wavelength DFB laser array with equivalent three shifts are also given. High lasing wavelength precision was obtained. This paper demonstrates that the REC technique is a promising way for fabricating the multiwavelength DFB laser array with low cost and high yield.

Multiwavelength DFB laser array with integrated spot size converters

We describe the design, fabrication, and performance of a five-element quarterwave-shifted distributed feedback laser array with monolithically integrated spot size converters intended for use as a multiple-wavelength source in dense wavelength-division telecommunications systems. Facet power in excess of 10 mW with less than 150 mA bias and longitudinal side mode suppression greater than 40 dB were routinely achieved. Narrow far-field full-width at half-maximum angles of 6.9/spl deg//spl times/16.3/spl deg/ provided 3.5-dB coupling loss into single-mode fiber with 1.0-dB misalignment tolerances of /spl plusmn/2.0 /spl mu/m. With /spl plusmn/10/spl deg/C thermal tuning, 22 1555-nm channels spaced by 50 GHz were accessed with this device. Thorough field evaluation indicates that such a device is consistent with manufacturing requirements.

Multiwavelength DFB laser arrays with integrated combiner and optical amplifier for WDM optical networks

In this paper, we describe the design, fabrication and performance of multiwavelength DFB laser arrays with integrated combiner and optical amplifier built for wavelength-division-multiplexed (WDM) optical networks. The goal is to reduce the per-wavelength transmitter cost in both initial procurement and subsequent operation. Using photonic integration, we have addressed and resolved several important issues related to laser arrays such as wavelength accuracy, output power, high-speed modulation and optical packaging. State of the art results have been obtained. By the use of wavelength redundancy and proximity effect, wavelength deviations of /spl plusmn/0.2 nm or less from the designated eight-wavelength comb have been achieved with high yield. Simultaneous operation of ten wavelengths has also been demonstrated. In spite of the inherent splitting loss of 13 dB, high-output powers of about -13 and 0.5 dBm per wavelength have been measured, under simultaneous operation, into a single-mode fiber (SMF) without and with on-chip optical amplification, respectively. The DFB laser has a 3-dB bandwidth of 9 GHz. A 2.5-Gb/s (OC-48) error-free transmission through 120 km conventional SMF has been demonstrated under single channel operation. The electrical crosstalk from neighboring channels cause negligible degradation to the eye diagram and the bit-error-rate (BER) curve at a bit rate of 2.5 Gb/s. The optical crosstalk due to four-wave mixing and cross-gain modulation (XGM) of the semiconductor optical amplifier (SOA) is also characterized. The impact of this integrated laser array on WDM optical networks is assessed in the conclusion.

Wavelength accuracy and output power of multiwavelength DFB laser arrays with integrated star couplers and optical amplifiers

In this letter, we report the static performance of multiwavelength DFB laser arrays with integrated star couplers and optical amplifiers built for the reconfigurable optical network testbed. By the use of wavelength redundancy and proximity effect, wavelength deviations of /spl plusmn/0.2 nm or less from the designated eight-wavelength comb have been achieved with high yield. Simultaneous operation of eight wavelengths has also been demonstrated. In spite of the inherent splitting loss of 13 dB, high output powers of about -13 dBm and 0 dBm per wavelength have been measured into a single-mode fiber without and with on-chip optical amplification, respectively.

Multiwavelength DFB laser array transmitters for ONTC reconfigurable optical network testbed

We discuss the design, fabrication, and performance of experimental multiwavelength laser array transmitters that have been used in the reconfigurable optical network testbed for the Optical Network Technology Consortium (ONTC). The experimental four-node multiwavelength network testbed is SONET/ATM compatible. It has employed multiwavelength DFB laser arrays with 4 nm wavelength spacing for the first time. The testbed has demonstrated that multiwavelength DFB laser arrays are indeed practical and reproducible. For the DFB laser arrays used in such a network the precise wavelength spacing in the array and the absolute wavelength control are the most challenging tasks. We have obtained wavelength accuracy better than /spl plusmn/0.35 nm for all lasers, with some registered to better than /spl plusmn/0.2 nm. We have also studied the array yield of our devices and used wavelength redundancy to improve the array yield. Coupling efficiencies between -2.1 to -4.5 dB for each wavelength channel have been obtained. It is achieved by using specially designed lensed fiber arrays placed on a silicon V-grooved substrate to exactly match the laser spacing. The transmitter consisted of a multichip module containing a DFB laser array, an eight-channel driver array based on GaAs IC's, and associated RF circuitry.

Monolithic Integrated Multi-wavelength DFB Laser Arrays and Star Couplers for WDM Lightwave Systems

Monolithic Integrated Multi-wavelength DFB Laser Arrays and Star Couplers for WDM Lightwave Systems