Huapeng Ruan

Vertical Bridgman growth and optical properties of CdSiP2 crystals

Single crystals of CdSiP2 (CSP) with the dimension of 8 mm in diameter and 40 mm in length were successfully grown using vertical Bridgman method. Optical observations showed the presence of macro-defects including flaws and inclusions in the as-grown crystals. The macro-defects can be restrained through controlling the process of polycrystalline synthesis and growth parameters. For the crystals with improved qualities, the high-resolution X-ray diffraction measurement on the (004)-faced plate indicates that the full-width at half-maximum (FWHM) of the rocking curve is 34′′. The phase-matching curves calculated from refractive indices indicate that, for 1.064 μm pumping, the CSP crystal will produce a noncritically phase-matched output at 6.2 μm through a type-I parametric process, and a noncritically phase-matched output at 5.0 μm through a type-II parametric process. For 1.55 μm and 2.00 μm pumping, the crystal yields continuous tunability from 2 to 6.5 μm through a type-I parametric process. The absorption coefficients for e-polarized light at 1.064 μm, 1.55 μm and 2.0 μm of the as-grown CSP crystal are 0.53 cm−1, 0.39 cm−1, and 0.25 cm−1, respectively.

Flux growth and characterization of an FeSi4P4 single crystal

Herein, a single crystal of FeSi4P4 (FSP) with dimensions up to 8 × 7 × 3 mm3 was successfully grown using a seeded flux growth method. Single crystal X-ray diffraction results revealed that the FSP crystal crystallized in the chiral space group P1 (no. 1). High-resolution X-ray diffraction presents a full-width at half-maximum (FWHM) of 36′′ and 46′′ for the (100) and (001) FSP crystals, respectively, which indicates that FSP crystals have high crystalline quality. FSP is thermally stable up to 1157.1 °C and has a high thermal conductivity of 35 W (m K)−1 at room temperature. The magnetic analysis shows that the FSP crystal is paramagnetic in the range from 5 to 300 K. The Hall effect measurement suggests that the FSP crystal is a promising p-type semiconductor at room temperature.