Semiconductor physics and light-matter interaction
PHYS-433
Recorded version of Lecture 13
PHYS-433 Lecture 13
15.12.2021, 12:29
In this lecture, we first account for the dependence of the real part of the optical refractive index as a function of energy/wavelength below the bandgap of any dielectric media. It is thus shown that this quantity is proportional to the inverse of the bandgap of the system of interest.
We then describe in a qualitative manner the change in the absorption spectrum close to the band edge in doped semiconductors: the Burstein-Moss shift in n-type doped semiconductors (i.e., the blueshift of the absorption edge with increasing n-type doping) and the redshift of the absorption edge with increasing p-type doping. Such a modification is shown to be accompanied with the appearance of tail states.
Finally, the physics of excitons, i.e., electron-hole pairs bound by Coulomb interaction, in bulk semiconductors is described including their binding energy as derived from the hydrogenic model and their oscillator strength by generalizing Fermi's Golden Rule from the one-electron picture to the two-electron picture.
PHYS-433 Lecture 13
15.12.2021, 12:29
In this lecture, we first account for the dependence of the real part of the optical refractive index as a function of energy/wavelength below the bandgap of any dielectric media. It is thus shown that this quantity is proportional to the inverse of the bandgap of the system of interest.
We then describe in a qualitative manner the change in the absorption spectrum close to the band edge in doped semiconductors: the Burstein-Moss shift in n-type doped semiconductors (i.e., the blueshift of the absorption edge with increasing n-type doping) and the redshift of the absorption edge with increasing p-type doping. Such a modification is shown to be accompanied with the appearance of tail states.
Finally, the physics of excitons, i.e., electron-hole pairs bound by Coulomb interaction, in bulk semiconductors is described including their binding energy as derived from the hydrogenic model and their oscillator strength by generalizing Fermi's Golden Rule from the one-electron picture to the two-electron picture.
PHYS-433 Lecture 13
15.12.2021, 12:29
In this lecture, we first account for the dependence of the real part of the optical refractive index as a function of energy/wavelength below the bandgap of any dielectric media. It is thus shown that this quantity is proportional to the inverse of the bandgap of the system of interest.
We then describe in a qualitative manner the change in the absorption spectrum close to the band edge in doped semiconductors: the Burstein-Moss shift in n-type doped semiconductors (i.e., the blueshift of the absorption edge with increasing n-type doping) and the redshift of the absorption edge with increasing p-type doping. Such a modification is shown to be accompanied with the appearance of tail states.
Finally, the physics of excitons, i.e., electron-hole pairs bound by Coulomb interaction, in bulk semiconductors is described including their binding energy as derived from the hydrogenic model and their oscillator strength by generalizing Fermi's Golden Rule from the one-electron picture to the two-electron picture.
PHYS-433 Lecture 13
15.12.2021, 12:29
In this lecture, we first account for the dependence of the real part of the optical refractive index as a function of energy/wavelength below the bandgap of any dielectric media. It is thus shown that this quantity is proportional to the inverse of the bandgap of the system of interest.
We then describe in a qualitative manner the change in the absorption spectrum close to the band edge in doped semiconductors: the Burstein-Moss shift in n-type doped semiconductors (i.e., the blueshift of the absorption edge with increasing n-type doping) and the redshift of the absorption edge with increasing p-type doping. Such a modification is shown to be accompanied with the appearance of tail states.
Finally, the physics of excitons, i.e., electron-hole pairs bound by Coulomb interaction, in bulk semiconductors is described including their binding energy as derived from the hydrogenic model and their oscillator strength by generalizing Fermi's Golden Rule from the one-electron picture to the two-electron picture.
PHYS-433 Lecture 13
15.12.2021, 12:29
In this lecture, we first account for the dependence of the real part of the optical refractive index as a function of energy/wavelength below the bandgap of any dielectric media. It is thus shown that this quantity is proportional to the inverse of the bandgap of the system of interest.
We then describe in a qualitative manner the change in the absorption spectrum close to the band edge in doped semiconductors: the Burstein-Moss shift in n-type doped semiconductors (i.e., the blueshift of the absorption edge with increasing n-type doping) and the redshift of the absorption edge with increasing p-type doping. Such a modification is shown to be accompanied with the appearance of tail states.
Finally, the physics of excitons, i.e., electron-hole pairs bound by Coulomb interaction, in bulk semiconductors is described including their binding energy as derived from the hydrogenic model and their oscillator strength by generalizing Fermi's Golden Rule from the one-electron picture to the two-electron picture.
PHYS-433 Lecture 13
15.12.2021, 12:29
In this lecture, we first account for the dependence of the real part of the optical refractive index as a function of energy/wavelength below the bandgap of any dielectric media. It is thus shown that this quantity is proportional to the inverse of the bandgap of the system of interest.
We then describe in a qualitative manner the change in the absorption spectrum close to the band edge in doped semiconductors: the Burstein-Moss shift in n-type doped semiconductors (i.e., the blueshift of the absorption edge with increasing n-type doping) and the redshift of the absorption edge with increasing p-type doping. Such a modification is shown to be accompanied with the appearance of tail states.
Finally, the physics of excitons, i.e., electron-hole pairs bound by Coulomb interaction, in bulk semiconductors is described including their binding energy as derived from the hydrogenic model and their oscillator strength by generalizing Fermi's Golden Rule from the one-electron picture to the two-electron picture.