Temperature‐Dependent Tip‐Induced Motion of Ga Adatom on GaAs (110) Surface

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 16; no. 32; pp. e2002296 - n/a
• Main Authors: Kaku, Shigeru, Yoshino, Junji
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.08.2020
• Subjects: Adatoms; atomic manipulation; Electronic structure; electronic structure calculations; Nanotechnology; Scanning tunneling microscopy; surfaces; temperature characteristics; Temperature dependence
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202002296

The temperature‐dependent tip‐induced‐motion of a Ga adatom on a GaAs (110) surface is experimentally demonstrated using scanning tunneling microscopy (STM). The surface adsorption energy profile obtained by first‐principle electronic structure calculations reveals that the origin of the Ga motion observed at 78 K is attributable to the tip‐induced Ga adatom hopping between the most stable potential minima among the three local minima, whereas that observed at 4.2 K is attributable to the tip‐induced hopping and sliding motions through the next stable minima as well as the most stable minima. Furthermore, it is shown that a slight progressive modification of the adatom motion observed only at 4.2 K resulting from repeated STM line scans is consistent with the overall picture taking account of the heating of the adatom owing to the tip current. Temperature dependent adsorption sites and tip‐induced motions of Ga adatoms on a semiconductor GaAs (110) surface are explored in a real space image using scanning tunneling microscopy (STM). The surface adsorption potential profile of the Ga adatom on the GaAs (110) obtained by first‐principles calculations successfully demonstrates oberved temperature depending phenomena.