High-power dual-fed traveling wave photodetector circuits in silicon photonics

Abstract

We introduce the concept of dual-illuminated photodetectors for high-power applications. Illuminating the photodetector on both sides doubles the number of optical channels, boosting DC and RF power handling capability. This concept is demonstrated utilizing multiple-stage dual-illuminated traveling wave photodetector circuits in silicon photonics, showing a maximum DC photocurrent of 112 mA and a 3-dB bandwidth of 40 GHz at 0.3 mA. Peak continuous-wave RF power is generated up to 12.3 dBm at 2 GHz and 5.3 dBm at 40 GHz, at a DC photocurrent of 55 mA. High speed broadband data signals are detected with eye amplitudes of 2.2 V and 1.3 V at 10 Gb/s and 40 Gb/s, respectively. A theoretical analysis is presented illustrating design tradeoffs for the multiple-stage photodetector circuits based on the bandwidth and power requirements.

A Wideband On-Chip Radiator Driven by a Traveling-Wave Photodetector

“…1a). This reduction in germanium area allows higher optical powers to be absorbed, and feeding from both ends of the photodetector increases efficiency [6]. For an individual TWPD, the photodetectors are placed in parallel as part of the transmission line between the GSG pads [7], in which one side is a termination (L) and the other side is the receiver (S) (see Fig.…”

Silicon photonics traveling wave photodiode with integrated star coupler for high-linearity mm-wave applications

“…By adding a splitter in front of the PD, the linearity can be improved at the cost of a slight increase in insertion loss (due to the excess loss of the splitter, which is specified to be below 0.2 dB). This enhanced power handling capability is caused by the increased portion of the absorption layer that is used for the opto-electronic conversion [14].…”

“…To make optimal use of the aforementioned benefits of silicon photonics, a high-power variant of the existing Si-integrated Ge PiN photodetector needs to be constructed without altering the technology stack of the iSiPP25G platform or requiring heterogeneous integration. The traveling wave photodiode (TWPD) structure is the most popular configuration to realize high power handling while relying on high-speed p-i-n photodetectors [14]. In this paper, a highpower-handling traveling wave photodetector (TWPD) structure integrated on a silicon photonics waveguide platform will be discussed.…”

Markov chain Monte Carlo methods for statistical analysis of RF photonic devices

“…In this approach, a foundry service provides crosssection information and models of building blocks to clients, who design a photonic integrated circuit (PIC) [1] to fit their own specific needs. Recent demonstrations of high-speed PICs fabricated using foundry services [2][3][4] have shown that it is possible to design PICs with performance better than that of single building blocks. In order for first-time-correct designs to become consistently achievable, accurate microwave impedance models must be included in foundry libraries.…”