# Large-area Photocathodes (LAP)

Canonical: https://abierto.us/opportunities/darpaps2501

- Solicitation number: DARPA-PS-25-01
- Notice type: Solicitation
- Status: Closed. Deadline was December 18, 2024 at 5:00 PM EST
- Department: Department of Defense
- Agency: Defense Advanced Research Projects Agency
- Contracting office: Def Advanced Research Projects Agcy (HR0011)
- NAICS: 541715 Research and Development in the Physical, Engineering, and Life Sciences (except Nanotechnology and Biotechnology)
- Product or service code: AC13 National Defense R&D Services; Department Of Defense - Military; Experimental Development
- First posted: November 20, 2024
- Last posted: December 10, 2024
- SAM.gov: https://sam.gov/workspace/contract/opp/0f5b3fb07d6d416c8b6ea38349751614/view

## Description

The LAP program seeks to develop large-area photocathodes. Photocathodes can be found in devices such as photomultiplier tubes, image intensifiers, high-power electronics, and even free electron lasers. Photocathodes typically use low-work function metals or semiconductors and are applied in sub-micron thicknesses on planar surfaces with millimeter to centimeter-scale areas. Photocathode performance can be characterized by attributes such as quantum efficiency (QE), lifetime, and mean transverse energy (MTE).

Metals such as copper and magnesium have low QE but are well-understood, robust, and easy to obtain. CsTe is a leading semiconductor used within the accelerator community with a reasonable balance of QE, lifetime, and MTE. Diamond has been examined for switching applications but may hold promise as a photocathode. Other materials, such as the alkali antimonides, could offer high QE operation at longer wavelengths but may have lifetime, process, and handling challenges.

In addition, recent work has also focused on increasing QE and lowering emittance through patterning techniques. , LAP seeks manufacturable photocathode material systems with high quantum efficiency that can be produced in large areas with substantial lifetimes and manageable handling requirements. LAP will develop and produce photocathodes that will be incorporated by the government team into a prototype system.

## Publications

- November 20, 2024: Solicitation, due December 18, 2024. Notice 2fa6512d118d4f3b868fdb606948fdef. https://sam.gov/workspace/contract/opp/2fa6512d118d4f3b868fdb606948fdef/view
- December 10, 2024: Solicitation, due December 18, 2024 at 5:00 PM EST. Notice 0f5b3fb07d6d416c8b6ea38349751614. https://sam.gov/workspace/contract/opp/0f5b3fb07d6d416c8b6ea38349751614/view

## Points of contact

- BAA Coordinator, DARPA-PS-25-01@darpa.mil

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Source: SAM.gov Contract Opportunities bulk extract. Confirm deadlines on SAM.gov before responding. Cite https://abierto.us/opportunities/darpaps2501.