Akihiro KIRIHARA, Shunsuke KONO, Akihisa TOMITA and Kazuo NAKAMURA¹

Fundamental and Environmental Research Laboratories, NEC corporation, 34 Miyukigaoka, Tsukuba, Ibaraki 305-8501, Japan
¹National Institute for Material Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan

(Received November 15, 2005; Accepted March 3, 2006)

We report on the development of a cantilever-based scanning near-field optical microscope (SNOM) working in an extreme environment, at cryogenic temperature around 10 K and under strong magnetic field up to 7 T. We designed a new optical system based on an infinite conjugate microscope, which extracts the near-field signal from a small aperture through a narrow chamber into free space as collimated light. Using this system, we successfully measured near-field and topographical images of a metal-hole sample simultaneously. Combining the local optical accessing technique with the external control of the electronic state, this SNOM system will be a powerful tool to study optical properties of semiconductor nanostructures.

Key words: SNOM, AFM, cantilever, magnetic field, quantum dot, quantum device