Demonstration of a Mid-infrared silicon Raman amplifier

Varun Raghunathan,David Borlaug,Robert R Rice,Bahram Jalali

doi:10.1364/oe.15.014355

Abstract

We demonstrate, for the first time, a mid infrared silicon Raman amplifier. Amplification of 12 dB is reported for a signal at 3.39 micron wavelength. The active medium was a 2.5 cm long silicon sample that was pumped with 5ns pulses at 2.88 micron. Such a technology can potentially extend silicon photonics' application beyond data communication in the near IR and into the mid-IR world of remote sensing, biochemical detection and laser medicine. Challenges faced in the mid-IR regime such as a higher free carrier scattering rate longer lifetime in mid-IR waveguides are also discussed.

Highlights

Silicon Photonics in the near infrared wavelength region has attracted significant attention in recent years with the aim of realizing low cost, high speed optoelectronic components for data and tele-communication applications
The maximum output power of these Raman devices is still limited by the nonlinear losses and the presence of free carriers increases the on-chip heat dissipation [5]
There is a need for efficient and versatile amplifiers in the Mid Wave Infrared (MWIR) to be used in power-scalable master oscillator power amplifier (MOPA) systems

Summary

Introduction

Silicon Photonics in the near infrared wavelength region has attracted significant attention in recent years with the aim of realizing low cost, high speed optoelectronic components for data and tele-communication applications. Typical laser sources developed for this wavelength range include diode pumped optical parametric oscillators [11], doped solid state lasers [12] and solid state (non semiconductor) Raman sources [13,14] These sources have not achieved wide spread use owing to the complexity, high cost of implementation and poor reliability. There is a need for efficient and versatile amplifiers in the MWIR to be used in power-scalable master oscillator power amplifier (MOPA) systems Another new application is the recently proposed image pre-amplifiers [15]. The paper starts with a brief description of the theory of Raman and other associated nonlinear optical effects with relevance to wavelength scaling This is followed by the experimental set-up, results, and discussions

Stimulated Raman scattering

Nonlinear absorption

Conclusions