The nearly-free electron model, Physics

Assignment Help:

Consider an electron in a simple one-dimensional periodic potential. The energy of the electron will vary periodically due to the influence of the periodic potential, and can be described by an energy-wavevector relation:
E(k)=-Acos(ka)
where a is the lattice constant and k is the Bloch wavevector.
a) Obtain an expression for the velocity of a wavepacket as a function of k

Related Discussions:- The nearly-free electron model

Dipole moment, what is the electric field when both the charges are same in...

what is the electric field when both the charges are same in dipole

Vectors, The helicopter view in fig. p3.29

The helicopter view in fig. p3.29

Which is most malleable, The most malleable, ductile low resistivity materi...

The most malleable, ductile low resistivity material is (A) Copper. (B) Aluminium. (C) Silver. (D) Iron. Ans: The most malleable, ductile low resistivity mater

What is the electric potential in hollow conducting shell, Five coulombs of...

Five coulombs of charge are placed on a thin-walled conducting shell. Once the charge has come to rest, the electric potential in the hollow conducting shell is found to be:

Determine the wavelength- amplitude - frequency and velocity, Displacement ...

Displacement related with a wave is given by y (x, t) = 0.1 cos(0.2x-2t). Where x y are in cm and ‘t' in second. Determine the wavelength, amplitude, frequency and velocity.

What is index fiber, What is index fiber? How you define the modes in an op...

What is index fiber? How you define the modes in an optical fiber? Give a relation between core diameter and numerical aperture. Ans.: The index profile of a single mode fi

What is normal reaction, What Is Normal Reaction ?How To Find It? Norm...

What Is Normal Reaction ?How To Find It? Normal reaction is the force acting among two contact surfaces. Like, if you push a wall, you will feel an opposite force acting on yo

What is hystersis, The lagging of an effect behind its cause; especially th...

The lagging of an effect behind its cause; especially the phenomenon in which the magnetic induction of a ferromagnetic material lags behind the changing magnetic field.

Direction south to north, An alpa particle is directed vertically upward wi...

An alpa particle is directed vertically upward with a speed of 3 X 104 Km/Sec in a region where a magnetic field of magnitude 1 Tesla exists in the direction south to north. Determ

Explain phase advancers, Phase advancers: Phase advancers are used to bett...

Phase advancers: Phase advancers are used to better the power factor of induction motors. The low power factor of an induction motor is because of the fact that its stator winding

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages