Electrically-injected tunable parametric source – SPAIN

The Optical Parametric Oscillator (OPO) is a well-known optical instrument, which from a functional point of view is a coherent, wavelength-tunable source. Like the laser, it is based on an optical amplifier in a resonant cavity. Unlike the laser, it relies on a parametric amplification instead of population inversion. This project aims to demonstrate the first electrically pumped OPO. This will be a major scientific breakthrough because, unlike the laser, whose heterostructure diode version has boosted the field of photonics with a high societal and economic impact, the search for a monolithic OPO with electric injection is still open half a century after the first OPO demonstration.
Today OPOs, pumped by conventional lasers, are available in different temporal, spectral and power formats. Much of the related technology is coming to maturity for several industrial, military, health and environmental applications, and new commercial products are being introduced to an ever-growing market. However, most of this market is still very research-related, mainly because of the limited portability of current OPOs. This limitation could be overcome by the SPAIN source which is the subject of this project and which will emit in the continuous-wave regime in the infrared between 1.5 and 2.5 microns. The SPAIN source that we will develop is an OPO monolithically integrated to a quantum-well laser diode, the two structures being linked by a vertical coupling. This design stems from the conclusions of an ANR project and a thesis co-funded by DGA, which had the same objective but in a single quantum-dot laser waveguide. However, the implementation of a design based on a single cavity, both laser and OPO, came up against narrow manufacturing tolerances and insufficient degrees of freedom to fulfil the phase matching condition. The new design, based on two distinct cavities and two independent temperature controls, will finally produce the first electrically injected OPO.
In the major interest technological field of photonics, the demonstration of such an OPO would be a major breakthrough in the spectral window between 2 and 3 µm, which is widely used for civilian applications such as gas detection, security and medical applications, as well as military applications. The availability of integrated components for this spectral range remains extremely limited, the devices operating in this region being limited to self-contained, narrow-band sources.
The availability of the SPAIN source would bring about a revolution in this field, due to its compactness, broad tunability, energy efficiency and low cost, with a potential impact on sensors for military, environmental or medical surveillance. As far as intellectual property and technology transfer are concerned, the same reasons that explain the exceptional performance of the laser diode (compactness, low cost, high plug efficiency) would boost the industrial prospects of the first SPAIN source.
The partners have internationally recognized complementary expertise in non-linear optics and semiconductor laser technology. Finally, the presence of Thales and Nokia's industrial partners through the III-V Lab, with their excellent results in the development and marketing of new advanced optoelectronic products, considerably enhances the prospects for the development of the SPAIN project.