Ultrafast scanning tunneling microscopy using a photoexcited low-temperature-grown GaAs tip

Author

Donati, G.P. ; Some, D. ; Rodriguez, G. ; Taylor, A.J.

Author_Institution

Div. of Mater. Sci. & Technol., Los Alamos Nat. Lab., NM, USA

fYear

1998

fDate

3-8 May 1998

Firstpage

537

Lastpage

538

Abstract

Summary form only given. We describe a novel STM tip consisting of a cleaved GaAs substrate with a 1 /spl mu/m-thick epilayer of low temperature-grown GaAs (LT-GaAs) deposited on the face. Because the LT-GaAs has a carrier lifetime of 1 ps, photoexcitation of the tip with an ultrafast, above bandgap pulse both provides carriers for the tunneling current and photoconductively gates (with ps resolution) the current from the tip. We use this tip to detect picosecond transients on a coplanar stripline and demonstrate a temporal resolution of 1.2 ps in tunneling mode.

Keywords

III-V semiconductors; epitaxial growth; gallium arsenide; high-speed optical techniques; scanning tunnelling microscopy; semiconductor growth; strip lines; 1 ps; 1.2 ps; GaAs; STM tip; carrier lifetime; cleaved GaAs substrate; coplanar stripline; epilayer; low temperature-grown GaAs; photoconductively gates; photoexcitation; photoexcited low-temperature-grown GaAs tip; picosecond transients; ps resolution; temporal resolution; tunneling current; tunneling mode; ultrafast above bandgap pulse; ultrafast scanning tunneling microscopy; Annealing; Gallium arsenide; Microscopy; Optical devices; Optical materials; Optical refraction; Pulse measurements; Temperature; Tunneling; Ultrafast optics;

fLanguage

English

Publisher

ieee

Conference_Titel

Lasers and Electro-Optics, 1998. CLEO 98. Technical Digest. Summaries of papers presented at the Conference on

Conference_Location

San Francisco, CA, USA

Print_ISBN

1-55752-339-0

Type

conf

DOI

10.1109/CLEO.1998.676600

Filename

676600