Charge States of DX Centers and Electronic Raman Scattering in n-Ga_(1-x)Al_(x)As

The observation of the electronic Raman scattering in n-Ga_(1-x)Al_(x)As(x>0.45)is reported and the charge state of DX centers in III-V alloy semiconductors is discussed.The result shows clearly that the electronic Raman scattering in n-Ga_(1-x)Al_(x)As of indirect band-gap and the persistent photoconductivity in n-Ga_(1-x)Al_(x)As of direct band-gap are equivalent to each other.Both of them originate from the optical induced metastable state of donors in n-Ga_(1-x)Al_(x)As(x>0.22)at low temperatures.At higher temperatures,this hydrogen-like level is depopulated to the benefit of a stable DX-like deep state.