Efficient Gap-Free Broadband Terahertz Generators Based on New Organic Quinolinium Single Crystals

Cited 1 time in webofscience Cited 0 time in scopus
  • Hit : 91
  • Download : 0
New organic electro-optic crystals containing orthogonally oriented electron-withdrawing groups are developed for efficient and gap-free THz wave generation with a very flat broadband spectral shape. These crystals consist of 2-(4-hydroxystyryl)-1-methylquinolinium (OHQ) cationic chromophores and nonplanar 4-(trifluoromethoxy)benzenesulfonate (TFO) anions with orthogonally oriented highly electronegative trifluoromethoxy groups capable of strong hydrogen bonds. OHQ-TFO crystals exhibit enhanced macroscopic optical nonlinearity with a second harmonic generation efficiency 2.3 times greater than that of benchmark OHQ-based crystals with conventional planar anions. This enhancement is attributed to reduced edge-to-face π–π interactions between cations and anions due to the orthogonal orientation and electron-withdrawing characteristics of trifluoromethoxy groups. Moreover, OHQ-TFO crystals exhibit excellent THz wave characteristics generated by optical rectification; 0.52 mm thick OHQ-TFO crystal generate a peak-to-peak THz electric field 15 times higher than that of inorganic standard 1.0 mm thick ZnTe crystal and a broader spectrum with an upper cut-off frequency near 8 THz at pump wavelengths of 1140–1500 nm. Unlike previously reported state-of-the-art organic electro-optic salt crystals with strong phonon absorption in the frequency range of 0.8–3 THz, OHQ-TFO crystals facilitate gap-free broadband THz wave generation without strong absorption modulations due to the strong hydrogen bond ability of trifluoromethoxy groups.
Publisher
WILEY-V C H VERLAG GMBH
Issue Date
2019-11
Language
English
Article Type
Article
Citation

ADVANCED OPTICAL MATERIALS, v.7, no.21, pp.1900953

ISSN
2195-1071
DOI
10.1002/adom.201900953
URI
http://hdl.handle.net/10203/268882
Appears in Collection
PH-Journal Papers(저널논문)
Files in This Item
There are no files associated with this item.
This item is cited by other documents in WoS
⊙ Detail Information in WoSⓡ Click to see webofscience_button
⊙ Cited 1 items in WoS Click to see citing articles in records_button

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0