Details

Autor(en) / Beteiligte

• Jeong, Chan‐Uk
• Kang, Bong Joo
• Lee, Seung‐Heon
• Lee, Seung‐Chul
• Kim, Won Tae
• Jazbinsek, Mojca
• Yoon, Woojin
• Yun, Hoseop
• Kim, Dongwook
• Rotermund, Fabian
• Kwon, O‐Pil

Titel

Yellow‐Colored Electro‐Optic Crystals as Intense Terahertz Wave Sources

Ist Teil von

• Advanced functional materials, 2018-07, Vol.28 (30), p.n/a

Ort / Verlag

Hoboken: Wiley Subscription Services, Inc

Erscheinungsjahr

2018

Quelle

Wiley Online Library

Beschreibungen/Notizen

• This study presents newly developed yellow‐colored organic electro‐optic crystals to provide high terahertz (THz) wave generation efficiency. Compared with currently existing red‐ or orange‐colored electro‐optic crystals, which are used for most benchmark organic THz sources, yellow‐colored crystals have additional superior advantages for THz wave generation, e.g., higher transparency in the visible wavelength range with accompanying different phase‐matching possibilities. The new yellow‐colored crystals consist of a highly nonlinear optical 4‐(4‐hydroxystyryl)‐1‐methylpyridinium (OHP) cation, with a relatively short wavelength of maximal absorption at 390 nm in solution, and various halogen‐substituted benzenesulfonate anions, with strong secondary‐bonding ability. OHP 4‐chlorobenzenesulfonate (OHP‐CBS) crystals exhibit large off‐resonant macroscopic optical nonlinearity and high transparency, with a cut‐off wavelength for solid‐state absorption near 490 nm. OHP‐CBS crystals provide excellent THz wave generation characteristics based on optical rectification. A 0.53 mm thick OHP‐CBS crystal delivers ≈27 times higher optical‐to‐THz conversion efficiency and a much broader spectrum bandwidth compared with the standard 1.0 mm thick ZnTe at 1300 nm pumping. Particularly, compared with a benchmark organic quinolinium crystal with a similar thickness of 0.55 mm, OHP‐CBS crystals exhibit 1.7 times higher optical‐to‐THz conversion efficiency, and show a significantly different THz spectral shape. Yellow‐colored electro‐optic salt crystals possessing large macroscopic optical nonlinearity with wide transparency exhibit excellent THz wave generation characteristics with significantly different THz spectral shapes compared with red‐ or orange‐colored benchmark organic electro‐optic crystals.