Nb₃Sn is a promising alternative to bulk Nb for superconducting radiofrequency (SRF) cavities due to its higher critical temperature (Tc ~18.3 K) and superheating field (Hsh ~400 mT), enabling improved cryogenic efficiency. Nb₃Sn coating method for superconducting radiofrequency (SRF) cavity has been developed following co-sputtering of Nb-Sn composite target using a DC cylindrical sputter...
Superconducting radio frequency (SRF) cavities are the fundamental accelerating components of linear particle accelerators. Niobium is the material of choice for SRF cavities due to its high malleability, thermal conductivity, and superconducting critical temperature (T_C). Despite Nb having a T_C of ~9 K, the practical operating temperature of a Nb SRF cavity is ~2 K, below the boiling point...
The success of electron cooling [1,2] for the Electron-Ion Collider (EIC) relies on the development of high-performance photocathodes (PCs) for photoinjectors. Ideal PCs are expected to exhibit high quantum efficiency (QE), low emittance, long operational lifetime, and minimal dark current. Alkali antimonide photocathodes are strong candidates to meet these demanding requirements. Among them,...
The emission of photo-excited electrons through inelastic scattering mechanisms is demonstrated to be prevalent in both semiconductor and metal photocathodes. This type of Franck-Condon process requires an intermediate ‘particle’ to simultaneously satisfy momentum and energy resonant electron emission into the vacuum states; optical phonons in polar semiconductors and the reciprocal lattice...
Generation of ultralow-emittance electron beams with high brightness is critical for several applications such as ultrafast electron diffraction, microscopy, and advanced accelerator techniques. By leveraging the differences in work function and electronic structure between different materials, we enabled spatially localized photoemission, resulting in picometer-scale emittance from a flat...
