Novel Semiconducting Materials for High Brightness and Air Stable Photocathodes

Stanford researchers have developed a method of designing materials for air-stable and high-brightness photocathodes. Challenges with current photocathode materials' lie with in brightness and extreme air sensitivity. This method addresses those challenges by first identifying semiconducting materials with high-brightness, then selects those which are air-stable. High-brightness is evaluated by calculating the intrinsic emittance: lower intrinsic emittance leads to higher brightness when used as a photocathode. The software was able to identify 11 novel materials, with some displaying brightness 16x larger than current state-of the art materials.A machine learning algorithm then aids in the discovery of air stable materials in order to eliminate the need for ultra-high vacuum environments. The identified class of M₂O materials can be used as air-stable and high-brightness materials; overall they simplify fabrication, synthesis and storage of photocathodes while increasing their longevity.

Photo description: Photocathode material screening workflow.

Stage of Research