Description du projet
Le laser à microcavité, une percée pour la lumière ultraviolette
Le projet UV-LASE, financé par l’UE, a pour objectif de produire le premier laser à microcavité capable de générer de la lumière ultraviolette qui pourrait être appliqué au monde réel. Grâce aux travaux novateurs du projet, les pertes optiques élevées et les densités de défauts ne feront plus obstacle à la mise en œuvre de ce type de laser. L’approche du projet est basée sur une technique de membrane unique qui permet d’utiliser des lasers à cavité verticale avec des miroirs diélectriques hautement réfléchissants des deux côtés de la cavité – un concept de dispositif auparavant impossible à réaliser pour les lasers ultraviolets. La conception proposée permettra également de décupler la puissance de sortie optique, car elle offre un moyen de contourner l’antiguidage, un mécanisme de perte négligé dans les microcavités.
Objectif
Achieving ultraviolet (UV) emission has proven to be difficult, in particular for microcavity lasers due to high optical losses and defect densities. Our group, with a world-leading position in microcavity laser research, has identified new possibilities to combat these challenges in both ultraviolet and blue-emitting devices. By using these breakthroughs, we aim to develop the first electrically injected blue microcavity laser with good enough performance to be useful in real-world applications and project out of the blue and into the ultraviolet to realize the very first electrically injected UV microcavity laser. Our two recent breakthroughs are:
1. The discovery of an overlooked loss mechanism in microcavities and schemes to circumvent it. Our proposed designs to circumvent this unintentional anti-guiding are being implemented worldwide and have led to a tenfold increase in optical output power in blue lasers.
2. A unique membrane technique to enable microcavity lasers with highly reflective dielectric mirrors on both sides of the cavity – a device concept previously un-realizable for UV-lasers. The method is based upon electrochemical etching of the chemically inert material AlGaN (the material of choice for UV), which enables lift-off of device membranes with smooth surfaces from the substrate and mirror-deposition on the bottom side. Our recent demonstration of the world’s first thin-film, flip-chip UV-B LED with this technique holds great promises for microcavity lasers.
These two new approaches will be combined with a focused effort to circumvent the problem of low electrical conductivity of p-doped materials. We will strengthen our capabilities by developing tunnel junctions, allowing highly conductive n-doped material to be used throughout virtually the entire laser. This will drastically reduce losses, which cause degradation within minutes in blue microcavity lasers, and might be the only solution to electrically driven UV microcavity lasers.
Champ scientifique
Programme(s)
Régime de financement
ERC-COG - Consolidator GrantInstitution d’accueil
412 96 GOTEBORG
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