Home > Timetable > Session details > Contribution details

Contribution Invited Oral

Budker INP - Conference Hall
THz radiation aplication

FEL-pumped Silicon lasers based on hydrogen-like impurity centers

Speakers

  • Prof. Heinz-Wilhelm HÜBERS

Primary authors

Co-authors

Content

Hydrogen-like impurity centers in monocrystalline Silicon can be utilized for terahertz(THz) lasers. Several types of such lasers have been demonstrated. The lasers operate at low lattice temperatures under optical pumping with a free electron laser (FEL). They emit light frequencies between 1.2 and 6.9 THz. Dipole-allowed optical transitions between particular excited states of substitutional impurities are utilized. Population inversion induced by optical pumping with the FEL is achieved due to specific electron–phonon interactions inside the impurity atom. This results in long-living and short-living excited states of the impurity centers. Another type of THz laser utilizes stimulated resonant Raman-type scattering of photons by a Raman-active intracenter electronic transition. By varying the pump-laser frequency, the frequency of the Raman intracenter silicon laser can be continuously changed between at least 4.5 and 6.4 THz. In addition, fundamental aspects of the laser process provide new information about the peculiarities of electronic capture by shallow impurity centers in silicon, lifetimes of nonequilibrium carriers in excited impurity states, and electron–phonon interaction.