Spin waves are collective excitations of spins in magnetic materials, that can be used to transport and manipulate spin information in spintronic devices. In this work, we use the magnetic field...Show moreSpin waves are collective excitations of spins in magnetic materials, that can be used to transport and manipulate spin information in spintronic devices. In this work, we use the magnetic field generated by a radio frequency (RF) current in a microstrip to excite surface-confined Damon-Eshbach spin waves in an Yttrium Iron Garnet (YIG) thin film. First, we measure the propagating spin waves by recording the currents they generate via induction in a second microstrip. By sweeping the RF frequency, we map out the spin wave spectrum excited in the YIG. Next, we harness the spin associated to a nitrogen-vacancy lattice defect in diamond (NV center) to locally probe the magnetic stray fields generated by the spin waves. By monitoring the NV center’s electron spin resonance (ESR) contrast and Rabi frequency we register the spectrum of the spin waves in a unique way. Moreover, we directly observe the filter function decay of the spin wave’s magnetic field and characterise resonant spin wave excitation in a microstrip cavity. Finally, we use a single NV center embedded in an AFM scanning probe to directly image the wavefronts of spin waves in YIG. This was never done before and paves the way for magnon imaging at the nanoscale.Show less
We determined the spatial resolution of the new very low energy transmission electron microscopy technique called eV-TEM [1] and used it to image gold nanoparticles deposited on graphene in order...Show moreWe determined the spatial resolution of the new very low energy transmission electron microscopy technique called eV-TEM [1] and used it to image gold nanoparticles deposited on graphene in order to determine whether it is possible to image for example DNA and proteins with low energy electrons. By transferring graphene to a flat grid with small circular holes in it we created new samples with flatter, less wrinkled graphene that make performing eV-TEM easurements on graphene easier and increase their quality. We improved the alignment of the imaging system of the microscope and determined the resolution of eV-TEM using the new samples to image graphene. We found a method to deposit 10nm gold nanoparticles on graphene suitable for eV-TEM measurements and a method to deposit ferritin on graphene that we should be able to image as well. We conclude that the spatial resolution of the current set-up of eV-TEM is 10nm and that it is possible to image gold nanoparticles deposited on graphene with eV-TEM.Show less
