The quantification of surface acoustic waves (SAWs) in LiNbO3 piezoelectric crystals by stroboscopic X‐ray photoemission electron microscopy (XPEEM), with a temporal smearing below 80 ps and a spatial resolution below 100 nm, is reported. The contrast mechanism is the varying piezoelectric surface potential associated with the SAW phase. Thus, kinetic energy spectra of photoemitted secondary electrons measure directly the SAW electrical amplitude and allow for the quantification of the associated strain. The stroboscopic imaging combined with a deliberate detuning allows resolving and quantifying the respective standing and propagating components of SAWs from a superposition of waves. Furthermore, standing‐wave components can also be imaged by low‐energy electron microscopy (LEEM). Our method opens the door to studies that quantitatively correlate SAWs excitation with a variety of sample electronic, magnetic and chemical properties.

The different magnetic phases of the intermetallic compound Nd 5 Ge 3 are studied in terms of the specific heat, in a broad range of temperatures (350 mK-140 K) and magnetic fields (up to 40 kOe).The expected T 3 and T 3/2 terms are not found in the antiferromagnetic (AFM) and ferromagnetic (FM) phases respectively, but a gapped T 2 contribution that originates from a mixture of AFM and FM interactions in different dimensionalities under a large magnetocrystalline anisotropy, is present in both. An almost identical Schottky anomaly, that arises from the hyperfine splitting of the nuclear levels of the Nd 3+ ions, is observed in both phases, which leads us to state that the magnetic-field induced transition AFM→FM that the system experiments below 26 K consists in the flip of the magnetic moments of the Nd ions, conserving the average local moment.

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Ferromagnetic resonance (FMR) spectroscopy measurements were performed on NbRe/Co/NbRe trilayers in order to probe spin pumping across the superconductor/ferromagnet interface and to detect a possible presence of spin-triplet pairing in the superconducting NbRe layer. FMR spectra were acquired as a function of frequency, magnetic field, and temperature, and reveal that the Gilbert damping parameter associated with spin pumping remains almost constant as temperature goes down through the superconducting transition. Additionally, the dependence of the Gilbert damping parameter on the thickness of the NbRe layer in trilayers is used to determine the values of the spin mixing conductance at the interface (18-21 nm^{-2) and the spin diffusion length in the NbRe layer (7.1-12.5 nm). These findings may suggest that spin pumping would still be effective even though NbRe becomes superconducting, which would indicate that spin-triplet would be the dominant pairing mechanism. Future experiments are proposed in the light of these results.