[16p-B6-1~23] 12.2 Characterization and Materials Physics

6:30 PM - 6:45 PM JST(9:30 AM - 9:45 AM UTC)

[16p-B6-20] Energy band structure of image potential states of organic semiconductor on graphite studied by angle-resolved low-energy inverse photoelectron spectroscopy

〇(M1)Tomoko Onishi¹, Hiroyuki Yoshida^1,2 (1.Chiba Univ., 2.Chiba Univ.)

Keywords:

organic semiconductor,image potential states,effective mass

Using angle-resolved low-energy inverse photoelectron spectroscopy (ARLEIPS), we directly observed the band structure (energy and momentum dispersion relationship) of a monolayer of copper phthalocyanine (CuPc) on HOPG. We found that the electrons in the image potential state behave like free electrons, and we determined the effective masses of the image potential states on HOPG and CuPc/HOPG to be 1.14±0.02 and 1.33±0.08, respectively. The result can be interpreted that the periodic potential generated by CuPc molecules increases the effective mass of the image states.