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Plasmas are generally known as the hot gases of charged particles which behave classically under the action of electrostatic and electromagnetic forces. However, there are plasmas which don´t fall in this category. These are low temperature/high density plasmas in which the plasma particles become so close that the interparticle distances become comparable to the spatial extension of their wave functions. Such plasmas are found not only in dense astrophysical objects, but also in different laboratory settings and commonly termed as degenerate (quantum) plasmas. To model such plasmas is a challenging task owing to their complexities. However, semiclassical models are quite useful sometimes to investigate their collective behaviour. This text, investigates low frequency modes in quantum plasmas by using quantum hydrodynamic formulation. Quantum ion acostic, drift and Alfven modes are investigated. The scale lengths are found very short and quantum statistical effects significant. The ion solitary waves are also affected by quantum behaviour of electrons in such systems.

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The authos is assistant professor at National Centre for Physics, Islamabad Pakistan. His research interests lie in quantum and classical plasmas, nonlinear waves, complex plasmas and theoretical modeling. He has published more than 27 research articles in international journals and conference proceedings and a book chapter.

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