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In this study, the growth of scandium nitride (100) single crystals with high electron mobility and high thermal conductivity was demonstrated by physical vapor transport (PVT). Single crystals were grown in the temperature range of 1900 C–2140 C under a nitrogen pressure between 15 and 20 Torr. Single crystal tungsten (100) was used as a nearly lattice constant matched seed crystal. Growth for 20 days resulted in a 2mm thick crystal. Hall-effect measurements revealed that the layers were n-type with a 300 K electron concentration and a mobility of 2.17 x 1021 cm-3 and 73 cm2/V s, respectively. Consequently, this ScN crystal had a low electrical resistivity, 3.94 x 10- 5 Xcm. The thermal conductivity was in the range of 51–56W/mK, three times higher than those in previous reports for ScN thin films. This study demonstrates the viability of the PVT crystal growth method for producing high quality bulk scandium nitride single crystals.
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Engineering Order in the Lattice of LiNbO3 Crystal Written in Glass by Femtosecond Laser
Erbium doped single crystals of lithium niobate were grown within the bulk of 0.075 Er2O3 – 37 Li2O – 37 Nb2O5 – 26 SiO2 glass using a femtosecond pulsed laser. Combined excitation emission spectroscopy was used to show incorporation of erbium into the laser written crystal lattice. Laser power and scanning speed were held constant at optimized values, while bulk sample temperature was systematically varied to study the impact on the crystal growth. Using electron backscatter diffraction to study the transverse cross-sections of grown crystals, control over the lattice rotation rates and crystal size were realized. Unlike changing other parameters, a range of temperatures were found to have substantial impacts on crystal growth, without inhibiting the ability to maintain single crystal formation over long distances.
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- Award ID(s):
- 2123131
- PAR ID:
- 10583497
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Optical Materials
- Volume:
- 152
- Issue:
- C
- ISSN:
- 0925-3467
- Page Range / eLocation ID:
- 115514
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.optmat.2024.115514
