TY - JOUR
T1 - Characterizations of nonlinear optical properties on GaN crystals in polar, nonpolar, and semipolar orientations
AU - Chen, Hong
AU - Huang, Xuanqi
AU - Fu, Houqiang
AU - Lu, Zhijian
AU - Zhang, Xiaodong
AU - Montes, Jossue A.
AU - Zhao, Yuji
PY - 2017/5/1
Y1 - 2017/5/1
N2 - We report the basic nonlinear optical properties, namely, two-photon absorption coefficient (β), three-photon absorption coefficient (γ), and Kerr nonlinear refractive index (nkerr), of GaN crystals in polar c-plane, nonpolar m-plane, and semipolar (2021¯) plane orientations. A typical Z-scan technique was used for the measurement with a femtosecond Ti:S laser from wavelengths of 724 nm to 840 nm. For the two-photon absorption coefficient ( β), similar values were obtained for polar, nonpolar, and semipolar samples, which are characterized to be ∼0.90 cm/GW at 724 nm and ∼0.65 cm/GW at 730 nm for all the three samples. For the Kerr nonlinear refractive index (nkerr), self-focusing features were observed in this work, which is different from previous reports where self-defocusing features were observed on GaN in the visible and near-UV spectral regions. At 724 nm, nkerr was measured to be ∼2.5 0 × 10−14 cm2/W for all three samples. Three-photon absorption coefficients (γ) were also determined, which were found to be consistent with previous reports. This study provides valuable information on the basic nonlinear optical properties of III-nitride semiconductors, which are vital for a wide range of applications such as integrated photonics and quantum photonics.
AB - We report the basic nonlinear optical properties, namely, two-photon absorption coefficient (β), three-photon absorption coefficient (γ), and Kerr nonlinear refractive index (nkerr), of GaN crystals in polar c-plane, nonpolar m-plane, and semipolar (2021¯) plane orientations. A typical Z-scan technique was used for the measurement with a femtosecond Ti:S laser from wavelengths of 724 nm to 840 nm. For the two-photon absorption coefficient ( β), similar values were obtained for polar, nonpolar, and semipolar samples, which are characterized to be ∼0.90 cm/GW at 724 nm and ∼0.65 cm/GW at 730 nm for all the three samples. For the Kerr nonlinear refractive index (nkerr), self-focusing features were observed in this work, which is different from previous reports where self-defocusing features were observed on GaN in the visible and near-UV spectral regions. At 724 nm, nkerr was measured to be ∼2.5 0 × 10−14 cm2/W for all three samples. Three-photon absorption coefficients (γ) were also determined, which were found to be consistent with previous reports. This study provides valuable information on the basic nonlinear optical properties of III-nitride semiconductors, which are vital for a wide range of applications such as integrated photonics and quantum photonics.
UR - http://www.scopus.com/inward/record.url?scp=85018259459&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85018259459&partnerID=8YFLogxK
U2 - 10.1063/1.4983026
DO - 10.1063/1.4983026
M3 - Article
AN - SCOPUS:85018259459
VL - 110
JO - Applied Physics Letters
JF - Applied Physics Letters
SN - 0003-6951
IS - 18
M1 - 181110
ER -