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We report on the modulation of interlayer exchange coupling (IEC) between the ferromagnet (FM) Fe and insulating antiferromagnet (AFM) CoO and its impact on the Gilbert damping by a time-resolved magneto-optical Kerr effect technique. By inserting a wedge spin conductor Ag layer at the interface of Fe/CoO, it is revealed that both uniform spin precession frequency and Gilbert damping constant of Fe film decrease with increasing Ag thickness up to ∼2 nm, and above that with eliminated IEC, these two parameters reach the intrinsic values of the Fe film. The precession frequency and damping also show similar variation tendency with temperature for attenuated IEC. These results prove that the exchange coupling at the FM–AFM interface plays an essential role for the spin angular momentum transfer to the insulating AFM layer, and the spin pumping is insignificant even for the very thin spin conductor layer. Our findings may have general insights into the role of the FM/AFM interface in the magnetization dynamics and spin angular momentum transfer for future spintronic applications. [ABSTRACT FROM AUTHOR]

Yb:KLu(WO4)2 (KLuW) crystals with large size and good optical quality have been grown by the top-seeded solution growth (TSSG) method. The melting point and specific heat, anisotropic thermal expansion and thermal conductivity have been measured. The Jackson factor α of a series of observed faces (hkl) on Yb:KLuW crystals have been calculated. In addition, the microhardness has also been measured. We find that the thermal expansion anisotropy of Yb:KLuW is weaker than KGd(WO4)2 (KGW) and KYb(WO4)2 (KYbW) and the thermal conductivity is up to 4.4 W m-1 k-1 along [205] directions at 25 °C, which is the greatest in their family. [ABSTRACT FROM AUTHOR]

The nonlinear optical properties of C[SUB60][NH[SUB2]- (CH[SUB2])[SUB3] -Si(OC[SUB2]H[SUB5])[SUB3]][SUB3] sol and gel were investigated by femtosecond optical Kerr gate technique at 820 nm. The nonresonant third-order optical susceptibilities were measured to be 1.4×10[SUP-13] and 1.6×10[SUP-13] esu for the C[SUB60][NH[SUB2]- (CH[SUB2])[SUB3]- Si(OC[SUB2]H[SUB5])[SUB3] sol and gel, respectively, which are two orders larger than that of C[SUB60] molecule. [ABSTRACT FROM AUTHOR]