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Classical Free electron Theory Assumptions Success,Drawbacks, Drude
• Classical Free electro...
Kronig Penney Model Bands in Solids K P Model
• Kronig Penney Model Ba...
E-k Diagram, Difference Between Direct Indirect band gap (DBS IBS)
• E-k Diagram, Differenc...
What is Density of States (DOS)
• What is Density of Sta...
Effective mass in semiconductor
• Effective mass in semi...
Probability of Occupation, Fermi Energy, Fermi Level, Fermi Dirac Distribution Function
• Probability of Occupat...
What is Phonon
• What is Phonon in Soli...
Density: Per unit volume.
State: Allowed solution which satisfy the boundary condition.
Definition 1: The density of states gives the number of allowed electron (or hole) states per volume at a given energy.
Definition 2: The density of states (DOS) is essentially the number of different states at a particular energy level that electrons are allowed to occupy, i.e. the number of electron states per unit volume per unit energy.
DOS calculations allow one to determine the general distribution of states as a function of energy and can also determine the spacing between energy bands in semi-conductors . Derivation of density of states can be derived from basic quantum mechanics.
Applications:
The density of states plays an important role in the kinetic theory of solids.
The product of the density of states and the probability distribution function is the number of occupied states per unit volume at a given energy.
Bulk properties such as specific heat, paramagnetic susceptibility, and other transport phenomena of conductive solids depend on this function.