MRI: Acquisition of a Short-pulse Ti:Sapphire Laser for Terahertz Studies of Semiconductor Heterostructures

Macalester College, Saint Paul MN

Investigators

Abstract

With this award from the Major Research Instrumentation program Macalester College will be able to acquire a short Titanium-Sapphire laser for Terahertz studies of semiconductor heterostructures. The laser system will permit time-resolved spectroscopy of materials at terahertz and mid-infrared frequencies. Initial research will use the instrument to support the Principal Investigator's NSF-funded program to study spin and charge dynamics in semiconductors (NSF-RUI DMR-0074622). Projects will include ultrafast Terahertz spectroscopy of spin-dynamics in semiconductors; time-resolved measurements of magneto-plasma oscillations in semiconductors; and quantum transitions in strongly driven semiconductor quantum wells and heterostructures. The equipment will also support undergraduate research training in Photonics and Condensed Matter Physics at Macalester College. With this award from the Major Research Instrumentation program Macalester College will be able to acquire a short Titanium-Sapphire laser for Terahertz studies of semiconductor heterostructures. As the switching rates in electronic devices are pushed to ever higher frequencies, it becomes increasingly important to understand carrier transport phenomena in semiconductors on picosecond (10-12s) and femtosecond (10-15s) time-scales. Using ultrafast terahertz spectroscopy it is possible to impulsively excite a material with a femtosecond optical pulse or single-cycle electromagnetic pulse, and record the resulting motion of charge in time. This award supports equipment to enable time-resolved spectroscopy of materials at terahertz and mid-infrared frequencies. Initial research will use the instrument to support the Principal Investigator's NSF-funded program to study spin and charge dynamics in semiconductors (NSF-RUI DMR-0074622). The equipment will also support undergraduate research training in Photonics and Condensed Matter Physics at Macalester College.