Open AccessMolecular beam epitaxy of single unit-cell FeSe superconducting films on SrTiO3(001)
Author(s) -
王萌,
欧云波,
李坊森,
张文号,
汤辰佳,
王立莉,
薛其坤,
马旭村
Publication year - 2014
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.63.027401
Subject(s) - molecular beam epitaxy , scanning tunneling microscope , materials science , superconductivity , annealing (glass) , epitaxy , substrate (aquarium) , condensed matter physics , optoelectronics , nanotechnology , layer (electronics) , oceanography , physics , geology , composite material
Based on our previous work, we have systematically investigated the molecular beam epitaxy growth of single unit-cell FeSe films on SrTiO3(001) substrates and studied the surface morphology by scanning tunneling microscopy. We found that there are three key steps to obtain large-scale uniform one unit-cell superconducting FeSe films. First, the STO(001) substrates should be treated by HCl etching and thermal annealing under oxygen flux so that a specific TiO2-terminated STO(001) surface with well-defined step-terrace structure could be obtained. Second, the Fe and Se fluxes and substrate temperature have to be controlled delicately. At last, post-growth annealing is also critical, which can remove extra Se adatoms, and more importantly facilitate the necessary electron transfer for superconductivity transition.