55 GHz Bandwidth Distributed Reflector Laser

45 Gb/s Direct Modulation of Two-Section InP-on-Si DFB Laser Diodes

“…However, two-section laser diodes can also be useful in improving the modulation bandwidth. If beating happens between a main mode and a sufficiently weaker side mode, then the modulation bandwidth is enhanced at the beating frequency, as in [9]. The 3D-view and top-view of the laser structure are shown in Fig.…”

“…Simulations show that such designs can enhance the modulation bandwidth to values as high as 50 GHz due to the beating between the main mode and a closely-located side mode. An actual device utilizing this concept was fabricated and measured in [9], in which a monolithic InP DFB laser demonstrated a modulation speed of 112 Gbps. Here, the beating between the DBR and DFB modes, which are separated by 50 GHz, gives the modulation enhancement at 50 GHz.…”

Demonstration of 80 Gbps NRZ-OOK Electro-Absorption Modulation of InP-on-Si DFB Laser Diodes

“…For III-V-on-silicon devices, 56 Gbps NRZ-OOK electroabsorption modulation was demonstrated from both sides of the laser [2]. In [3], an InP distributed Bragg reflector (DBR) laser was used for the generation of 112 Gbps PAM-4. Furthermore, an InP-based double-side electroabsorption modulated DFB laser has been used for 2 x 56 Gbps PAM-4 [4].…”

“…For III-V-on-silicon devices, 25 Gbaud PAM-4 was demonstrated [2], and the same design was used for 100 Gbps EDB [5]. Although the bandwidth of direct modulation can be relatively high [3], modulation at high frequencies often comes with a large chirp. Electroabsorption modulation suffers less from this problem and its bandwidth is limited only by the RC-constant of the modulator.…”

A Low-Loss Split-Carrier Transmitter Architecture for Intra-Datacentre Communications

“…The CW launch power should be kept as low as possible to minimise the equipment and operational costs. To realise this, reduction of P mod,loss has been demonstrated using direct modulation, but requires nonlinear Volterra equalisation 2,3 . Alternatively, externally modulated lasers have enabled receiver sensitivities as low as −7.1 dBm at a BER of 3.8 × 10 −3 , but typically incur a 10 dB modulation loss 4 .…”