Spectroscopic signature of the Stark-shifted Tamm-type surface state of La(0001). (7th September 2020)

• Record Type: Journal Article
• Authors: Schreyer, Dominik; Kim, Howon; Wiesendanger, Roland
• Is Part Of: New journal of physics. Volume 22:Number 9(2020:Sep.)
• Publication Date: 2020-09-07
• Subjects: scanning tunneling microscopy -- scanning tunneling spectroscopy -- surface states -- Stark effect; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/ababc3
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: We have studied the Tamm-type surface state of La(0001) by tunneling spectroscopy within a wide range of tunneling currents from 0.1 nA to 8000 nA, thereby tuning the electric-field strength in a tip-vacuum-sample tunnel junction. We observe a significant shift of the unoccupied Tamm-type surface state toward the Fermi energy with increasing electric-field strength, accompanied by a broadening of the width of the resonance peak indicating a decrease of the surface-state lifetime. Our experimental results are contrary to previous reports for Stark-shifted Shockley-type surface states of noble metal (111) surfaces.