Ultra-broadband quantum-dot semiconductor optical amplifier and its applications

Abstract

We have developed an ultra-broadband InAs/InGaAsP quantum-dot semiconductor optical amplifier around 1520 nm with the 3-dB bandwidth of 150 nm. The four-wave mixing process and multi-wavelength lasers have been demonstrated by using our QD-SOAs.

Ultra-high repetition rate InAs/InP quantum dot mode-locked lasers

“…However, typically these sources only generate pulses with durations of greater than 1 picosecond (ps). It has been predicted for many years that replacing bulk and quantum wells (QWs) with quantum dots (QDs) as the active gain medium for semiconductor lasers should result in a number of enhancements in laser device performance, such as reduced threshold current density [3], lower sensitivity of the threshold current to temperature (T 0 ) [4], reduced chirp [5], much broad spectral gain bandwidths [6] and much faster carrier dynamics [7]. Recently, QD MLLs have received much attention [8] due to their inherent properties, leading to hopes of improved performance.…”

“…The proposed MLL mechanism need to be explained together with the QD gain materials' unique properties. Due to the statistically distributed sizes, geometries, compositions, and confinements, electrically pumped self-assembled QDs have highly imhomogeneously-broadened ASE spectra with the 3-dB bandwidth up to hundreds of nanometers [6]. Once those ASE spectra are laterally confined by waveguides, longitudinally selected and enhanced by a F-P cavity, lasing could occur over a broadwide wavelength range where intracavity gain is larger than waveguide internal loss plus cavity mirror losses.…”

Multiwavelength quantum-dot semiconductor fiber ring laser

“…The suitability of QD gain materials for multi-wavelength operation with better performance lies in the facts such as spectral hole-burning in broad inhomogeneous gain of QDs. Its inhomogeneous broadening of gain spectrum stems from statistically distributed sizes and geometries of self-assembled QDs, and its 3-dB bandwidth of up to 150 nm could be easily achievable [18], which provides a base for uniform and stable multi-channel operation. Each of lasing modes selected by an internal-cavity filters extracts only electrons in QDs resonant with the wavelength of that mode, depletes electrons in these QDs with the corresponding dot sizes.…”

“…Consequently, each mode consumes population inversion of differently localized carriers. This fast-recovery ultra-wide inhomogeneous broadening, as well as the spectral hole-burning within broad inhomogeneous gain of QDs will principally support stable multi-wavelength operation with high channel number and high uniformity of channel intensities [17,18]. Recently, we have designed, fabricated and characterized self-assembled InAs/InP QD-SOA devices around 1.55 µm.…”

“…Recently, we have designed, fabricated and characterized self-assembled InAs/InP QD-SOA devices around 1.55 µm. The experimental results [18] have shown that the 3-dB and 10-dB bandwidths of the amplified spontaneous emission (ASE) of the QD-SOA are 150 nm and 300 nm with the central wavelength of 1520, which is covering the S-, C-and L-band wavelength range. We have also demonstrated that a QDbased semiconductor waveguide Fabry-Perot (F-P) cavity chip with the desired coatings on the both facets was used to achieve MWLS [19,20].…”