Section 1: ELECTRON MICROSCOPIES
- Probes with high spatial resolution and state of the art in research and applications.
- Interaction of free electrons and bound electrons with matter.
- Information obtained by using electronic probes.
a) Far field electron microscopy
- Introduction to electron microscopy
- Diffraction limit and ray optics
- The scanning electron microscope (SEM)
- Interaction between electron and matter
- Secondary electron contrast
- Depth of field
- Charging and other imaging artifacts
- Back-scattered electron contrast
- Auger and X-ray Micro-spectroscopy probes in SEM
- The transmission electron microscope (TEM)
- Sample preparation
- Bright and dark field imaging
- The mass-thickness contrast
- Direct and reciprocal space imaging
- The diffraction contrast
- The phase contrast
- The scanning transmission electron microscope (STEM)
- Electron energy loss spectroscopy in STEM
- Ultrafast time resolution
b) Scanning probe microscopies
- Introduction to scanning probe microscopy
- Elements of a scanning-probe microscope
- Tip-sample forces
- Static AFM operation: constant height and constant force- Shift in the natural frequency of a harmonic oscillator under a force gradient
- Amplitude-modulation dynamic AFM operation
- Dynamic AFM operation: sensitivity in amplitude modulation, frequency-modulation techniques
- Noise and resolution in AFM
- Image analysis in AFM
- Magnetic force microscopy
- Other magnetic microscopy techniques
- Imaging artifacts in scanning probe microscopy
- Scanning near-field optical microscopy
- Super-resolution fluorescence microscopy
- Introduction to scanning tunneling microscopy
- Bardeen approach (time-dependent perturbation theory) to the tunneling current
- WKB approximation for the evaluation of the tunneling probability
- Atomic resolution with STM
- Scanning tunneling spectroscopy
Image analysis and practical testing of research instrumentation.
The couse will be held in the first half of the first term, from mid September to the beginning og November.
The range and detail of the course will be adapted to the level of the class during the course and may change significantly.
Section 2: SPINTRONICS
Micro and NANO magnetism
Demagnetizing field, magnetostatic energy. Landau magnetic free energy and its contributions (exchange, anisotropies, magnetostrictions). Domain walls. Micromagnetic simulations (OOMMF). Coherent magnetization reversal (Stoner Wohlfart model) and reversal via propagation of domain walls. Magnetic nanoparticles. Domain wall conduits. Magnetic coupling in multilayers (Néel coupling, Exchange bias, Bilinear coupling).
Two currents model and spin dependent scattering. Giant magnetoresistance in CIP and CPP configurations. Spin accumulation and Valet-Fert model. Tunneling magnetoresistance and magnetic tunneling junctions. Non volatile magnetic memories (MRAMs) and magnetic sensors. Spin transfer torque. Magneto-electric coupling. Spin injection, manipulation and detection in semiconductors.
Rashba based devices and Spin-FET. Spin currents. Direct and inverse spin Hall effect. Antiferromagnet spintronics.
Laboratory instruction in specific techniques of magnetic characterization of materials and devices will be provided, at the laboratory of Nanomagnetism located within the facility Polifab.