Development of a broadband superluminescent diode based on self-assembled InAs quantum dots and demonstration of high-axial-resolution optical coherence tomography imaging. (26th March 2019)

• Record Type: Journal Article
• Authors: Ozaki, Nobuhiko; Yamauchi, Sho; Hayashi, Yuma; Watanabe, Eiichiro; Ohsato, Hirotaka; Ikeda, Naoki; Sugimoto, Yoshimasa; Furuki, Kenji; Oikawa, Yoichi; Miyaji, Kunio; Childs, David T D; Hogg, Richard A
• Is Part Of: Journal of physics. Volume 52:Number 22(2019)
• Publication Date: 2019-03-26
• Subjects: quantum dot -- molecular beam epitaxy -- superluminescent diode -- optical coherence tomography; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/ab0ea5
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: We developed a near-infrared (NIR) superluminescent diode (SLD) based on self-assembled InAs quantum dots (QDs) and demonstrated high-axial-resolution optical coherence tomography (OCT) imaging using this QD-based SLD (QD-SLD). The QD-SLD utilized InAs QDs with controlled emission wavelengths as a NIR broadband light emitter, and a tilted waveguide with segmented electrodes was prepared for edge-emitting broadband electroluminescence (EL) spanning approximately 1–1.3 μ m. The bandwidth of the EL spectrum was increased up to 144 nm at a temperature of 25 °C controlled using a thermoelectric cooler. The inverse Fourier transform of the EL spectrum predicted a minimum resolution of 3.6 μ m in air. The QD-SLD was subsequently introduced into a spectral-domain (SD)-OCT setup, and SD-OCT imaging was performed for industrial and biological test samples. The OCT images obtained using the QD-SLD showed an axial resolution of ~4 μ m, which was almost the same as that predicted from the spectrum. This axial resolution is less than the typical size of a single biological cell (~5 μ m), and the practical demonstration of high-axial-resolution OCT imaging shows the application of QD-SLDs as a compact OCT light source, which enables the development of a portable OCT system.