Circularly Polarized Near-Field Optical Mapping of Spin-Resolved Quantum Hall Chiral Edge States

• Published in: Nano letters Vol. 15; no. 4; pp. 2417 - 2421
• Main Authors: Mamyouda, Syuhei, Ito, Hironori, Shibata, Yusuke, Kashiwaya, Satoshi, Yamaguchi, Masumi, Akazaki, Tatsushi, Tamura, Hiroyuki, Ootuka, Youiti, Nomura, Shintaro
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 08-04-2015
• Subjects: Circular Dichroism - instrumentation; Circularity; Diffraction; Equipment Design; Equipment Failure Analysis; Magnetic Fields; Mapping; Materials Testing - instrumentation; Microscopy, Scanning Probe - instrumentation; Nanomaterials; Nanostructure; Optical microscopes; Quantum Hall effect; Quantum Theory; Radiometry - instrumentation; Reproducibility of Results; Scanning; Sensitivity and Specificity; Spin Labels; nanophotonics; chiral; scanning probe microscopy; near-field optical microscope; circular polarization; quantum Hall effect; edge state; spin injection
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl504767w

We have successfully developed a circularly polarized near-field scanning optical microscope (NSOM) that enables us to irradiate circularly polarized light with spatial resolution below the diffraction limit. As a demonstration, we perform real-space mapping of the quantum Hall chiral edge states near the edge of a Hall-bar structure by injecting spin polarized electrons optically at low temperature. The obtained real-space mappings show that spin-polarized electrons are injected optically to the two-dimensional electron layer. Our general method to locally inject spins using a circularly polarized NSOM should be broadly applicable to characterize a variety of nanomaterials and nanostructures.