Investigating the Intrinsic Anisotropy of VO 2 (101) Thin Films Using Linearly Polarized Resonant Photoemission Spectroscopy

Condensed Matter

article

Alessandro D’Elia¹  Vincent Polewczyk³  Aleksandr Yu. Petrov³  Liang Li⁴  Chongwen Zou⁴  Javad Rezvani³  Augusto Marcelli¹ 

[1]CNR–Istituto Struttura della Materia, Basovizza Area Science Park

[2]Rome International Center for Materials Science Superstripes RICMASS

[3]Laboratorio TASC, Istituto Officina dei Materiali ,(IOM)–CNR, Area Science Park

[4]National Synchrotron Radiation Laboratory, University of Science and Technology of China

[5]Scuola di Scienze e Tecnologie, Sezione di Fisica, Università di Camerino

[6]Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare

关键词: VO2;    metal insulator transition;    bands anisotropy;    resonant photoemission;    electron correlation;    strained films;   

DOI  :  10.3390/condmat8020040

学科分类：社会科学、人文和艺术（综合）

来源: mdpi

【 摘 要 】

VO2 is one of the most studied vanadium oxides because it undergoes a reversible metal-insulator transition (MIT) upon heating with a critical temperature of around 340 K. One of the most overlooked aspects of VO2 is the band’s anisotropy in the metallic phase when the Fermi level is crossed by two bands: π* and d||. They are oriented perpendicularly in one respect to the other, hence generating anisotropy. One of the parameters tuning MIT properties is the unbalance of the electron population of π* and d|| bands that arise from their different energy position with respect to the Fermi level. In systems with reduced dimensionality, the electron population disproportion is different with respect to the bulk leading to a different anisotropy. Investigating such a system with a band-selective spectroscopic tool is mandatory. In this manuscript, we show the results of the investigation of a single crystalline 8 nm VO2/TiO2(101) film. We report on the effectiveness of linearly polarized resonant photoemission (ResPES) as a band-selective technique probing the intrinsic anisotropy of VO2.

【 授权许可】

CC BY