Spectroscopy Methods and Nanophotonics

Spectroscopy Methods and Nanophotonics


The aim of this course is to discuss different examples of Spectroscopy and Nanophotonics methods used in Condensed Matter Physics in the general framework of linear response theory.


6 Credits

Prof. Stefano Lupi


Generalities

  • General considerations on probe-target interaction; Equilibrium and out of Equilibrium;

  • Scattering matrix and linear response theorem; Detailed balance theorem; Examples of correlation functions for the various spectroscopies;

  • Spectroscopy in the frequency domain and in the time domain; Spatial and temporal resolution;

Arguments

  1. Scattering of thermal neutrons, generality and density-density correlation functions;

  2. Bragg peaks and long range order;

  3. Vibrational modes in a solid; Phononic dispersion; Density-density correlation function in liquids: Raleygh peak and Brillouin peaks;

  4. Electromagnetic field-matter interaction: correlation functions involved;

  5. Optical response of a Fermi liquid, Reflectivity, optical conductivity, dielectric function and refractive index; Phononic infrared absorption;

  6. Optical response of a superconductor;

  7. Absorption of IR radiation in biological systems; Infrared microscopy and diffraction limit; Field far and near;

  8. Scattering of the light, notes on the calculation of the term in A^2 in the potential vector; Correlation function polarizability-polarizability, physical meaning of polarizability;

  9. Scattering Brillouin and Raman;

  10. Ultra-fast lasers. Overview of non-linear optics.

  11. Measures out of thermodynamic equilibrium: Pump-Probe and ultrafast spectroscopy;

  12. Ultra-fast electronic response in metals and semiconductors;

  13. AFM microscopy techniques; SNOM and SNIM;

Other Topics

  • Magnetization-Magnetization correlation function and Magnetic Bragg Peaks;

  • Collective electronic excitations: Plasmons and electron scattering;

  • Applications of Infrared and Raman vibrational spectroscopy to cultural heritage;

  • Scattering of light and low-angle neutrons: disordered systems;

  • Absorption spectroscopy X: XANES and EXAFS;

  • Synchrotron light;

  • Electronic photoemission; Examples in metals and superconductors;

Exam Modality

The exam is oral and involves a question from the teacher on the program of the course, a topic to be enjoyed on the program and a paper (it is advisable to prepare a seminar with projectable slides) chosen from the following:

  • Plasmonic excitations and electron scattering (D. Davydov, Solid Physics);

  • Pump-Probe spectroscopy in metals and superconductors (R. Avereritt, J. Phys Condens. Matter 14 (2002) R1357-R1390);

  • Synchrotron radiation: properties and applications (Hercules Course: Neutron and Synchrotron Radiation for Condensed Matter Physics);

  • Small Angle Scattering book: Hercules Course: Neutron and Synchrotron Radiation for Condensed Matter Physics);

  • Optical properties of exotic electronic systems: superconductors and low-dimensional systems (Density Wave in Solids, A. Gruner)

  • X-ray absorption Spectroscopy (Neutron and Synchrotron Radiation for Condensed Matter Physics);

  • Spin waves and Neutron magnetic scattering (Solid Physics Davydov and Neutron and Synchrotron Radiation for Condensed Matter Physics);

  • Spectroscopic applications to cultural heritage (Infrared Spectroscopy in Conservation).


Bibliography

All arguments can be found in the teacher's notes. These notes should be integrated through the following books:

  • M. Dressel-G. Gruner, Optical Properties of Solids ;

  • Hercules Course: Neutron and Synchrotron Radiation for Condensed Matter Physics ;

  • L. Novotny, Principle of NanoOptics.