Phonon-coupled crystalline electric field effects in the Weyl semimetal candidate CeAlGe

CeAlGe crystallizes in a polar tetragonal structure (I41md, SG#109) where the symmetry-protected Weyl nodes are stabilized near the Fermi energy. Our preliminary experiments revealed a possible magneto-elastic coupling between the localized crystaline-electric-field doublet and the optical phonon at E ~ 17 meV. We aim to investigate the magneto-elastic effects unambiguously using the single-crystal CeAlGe by mapping out along the high-symmetric lines. Furthermore, the proposed experiment will give insight into the relation between the magneto-elastic coupling and Weyl fermions. Thus, we would like to request 3 days in the time-of-flight spectrometer Merlin with the typical orange cryostat.