Terahertz (THz) spectroscopy is an important tool to study properties of semiconductors to gain important insight into
materials. Generating THz radiation as freely propagating beam made THz Spectroscopy an ideal tool for investigating
various behaviors. Effect of THz-Time Domain Spectroscopic (THz-TDS) irradiation, applied to a potential well
structure, is considered here based upon an experimentally verified model. At ambient temperature, there will be two
mechanisms of scattering alongside others: charge-charge scattering and electron-phonon scattering as proposed by
Hendry et al. GaAs-AlxGa1-xAs double barrier heterostructure was selected. Mole fractions were chosen for which
appropriate Γ-band conduction energy differences were considered. Only optical phonon interactions were considered.
Effects of these mechanisms have been demonstrated in terms of broadening of transmission probabilities, group
velocity, phase coherence, quantum well transit time and most importantly, charge density against various pump
fluences. To get full impact of THz-TDS for charge density, modified Fermi distribution was considered and significant
results were obtained. An experimental setting emitting electron at different injection energy can be employed to
enumerate broadening in terms of plasma frequency and thus, pump fluence. Also, the impact of different elemental
compositions in the AlGaAs/GaAs or other resonant tunneling structures may be very precisely determined.