Magnetic skyrmions are topologically protected vortex-like nanometric spin textures that have recently received growingly attention for their potential applications in future highperformance spintronic devices. Such unique mangetic naondomains have been recently discovered in bulk chiral magnetic materials, such as MnSi [1][2][3][4] , FeGe [5,6] , FeCoSi [7] , Cu 2 OSeO 3 [8][9][10] , -Mn-type Co-Zn-Mn [11] , and also GaV 4 S 8[12] a polar magnet. The crystal structure of these materials is cubic and lack of centrosymmetry, leading to the existence of Dzyaloshinskii-Moriya (DM) interactions. Unlike the conventional spin configurations, such as helical or conical, that are usually found in chiral magnets, a magnetic skyrmion has a particle-like swirling-spin configuration characterized by a topological index called the skyrmion number [13,14] . The nontrivial topology of magnetic skyrmions results in a number of

Thin Pt films on an yttrium iron garnet (YIG = Y(3)Fe(5)O(12)) show ferromagneticlike transport properties, which may impact the functionality of Pt in spin current detection, but do not provide direct quantitative information on the Pt magnetization. We report magnetic x-ray magnetic circular dichroism measurements of YIG/Pt(1.5 nm) showing an average Pt moment of 0.054 μ(B) at 300 K and 0.076 μ(B) at 20 K. This observation indicates strong proximity effects and induced magnetic ordering in Pt on magnetic insulators and their contribution to the spin-related measurements should not be neglected. The transport characteristics also suggest considerable modifications in the Pt electronic structure due to magnetic ordering.