RESUMEN
We report bidirectional 25/28 GHz millimeter wave (MMW)-over-fiber (MMWoF) and MMWoF-wireless (MMWoF-WL) transmission systems employing a single self-injection locked InAs/InP quantum-dash dual-mode laser (QD-DML) as a MMW source. Besides, we demonstrate the entire system exploiting the challenging mid-L-band wavelength window (1610 nm) to substantiate this source's potential, which exhibits tunability from C- to L-bands, in next-generation optical networks covering these wavelengths' window operations. While exhibiting 28 GHz mode spacing between the two optical carriers of QD-DML, a downstream (DS) transmission of 4.0 Gbaud (8 Gbits/s) quadrature-phase-shift-keying (QPSK) signal is conducted over this carrier. In addition, a simultaneous 2.0 Gbaud (8 Gbits/s) 16-level quadrature amplitude modulation (16-QAM) upstream (US) transmission on a 25 GHz MMW beat-tone is also achieved by exploiting one of the DS optical tones. A rigorous transmission characterization of variable DS and US QPSK/16-QAM data rates over MMWoF (10 km SMF) and MMWoF-WL (10 km SMF and up to 4 m wireless) are performed, showing a strong influence of phase noise on the DS link and hence the receiver sensitivity.
RESUMEN
We report on the quantitative evidence of simultaneous amplified spontaneous emission from the AlGaInAs/InAs/InP-based quantum-well (Qwell) and quantum-dashes (Qdash) in a multistack dash-in-an-asymmetric-well superluminescent diode heterostructure. As a result, an emission bandwidth (full width at half-maximum) of >700 nm is achieved, covering entire O-E-S-C-L-U communication bands, and a maximum continuous wave output power of 1.3 mW, from this device structure. This demonstration paves a way to bridge entire telecommunication bands through proper optimization of device gain region, bringing significant advances and impact to a variety of cross-disciplinary field applications.
RESUMEN
A theoretical model is evaluated to investigate the characteristics of InAs/InP quantum dash (Qdash) lasers as a function of the stack number. The model is based on multimode carrier-photon rate equations and accounts for both inhomogeneous and homogeneous broadenings of the optical gain. The numerical results show a non monotonic increase in the threshold current density and a red shift in the lasing wavelength on increasing the stack number, which agrees well with reported experimental results. This observation may partly be attributed to an increase of inhomogeneity in the active region.
