Deep-ultraviolet near band-edge emissions from nano-polycrystalline diamond. Issue 1 (2nd January 2020)

• Record Type: Journal Article
• Authors: Ishii, Ryota; Fukuta, Rei; Ishikawa, Fumitaro; Matsushita, Masafumi; Ohfuji, Hiroaki; Shinmei, Toru; Irifune, Tetsuo; Funato, Mitsuru; Kawakami, Yoichi
• Is Part Of: High pressure research. Volume 40:Issue 1(2020)
• Page Start: 140
• Page End: 147
• Publication Date: 2020-01-02
• Subjects: Near band-edge emission -- luminescence spectroscopy -- Raman scattering spectroscopy -- electronic properties; High pressure (Science) -- Periodicals; High pressure (Technology) -- Periodicals; 536.41
• DOI: 10.1080/08957959.2019.1702658
• Languages: English
• ISSNs: 0895-7959

Abstract

ABSTRACT: Deep-ultraviolet continuous-wave photoluminescence spectroscopy is performed for nano-polycrystalline diamond (NPD) synthesized by a high pressure high-temperature technique. NPD exhibits clear deep-ultraviolet emissions, which originate from intrinsic excitonic transitions assisted by a momentum-conserving phonon with a photon. Surprisingly, the peak emission energy is about 30 meV higher than that of the single-crystalline diamond. Raman scattering spectroscopy indicates that the energy difference should originate from the excitonic properties of the NPD and not the phonon. Hence, NPD has a large bandgap compared to single-crystalline diamond.