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

How newton''s ring can be obtained in the laboratory, Q. Explain how Newt...

Q. Explain how Newton's ring can be obtained in the laboratory. Why Newton's rings are circular in shape? How the Newton's rings are used to find refractive index of liquid?

What type of material in optical fibres used, What type of material in opti...

What type of material in optical fibres used? Material in optical fibres: Optical fibres are generally made along with two kinds of materials that are glass (silica) and pla

Rotational equilibrium, A light horizontal bar has a length of 3m. If a 102...

A light horizontal bar has a length of 3m. If a 102-kg mass is placed 80 cm away from the left end of the bar and a 109-kg mass is placed 2.15 m from the left end, where must it be

A longitudinal wave moves through a medium, As a longitudinal wave moves th...

As a longitudinal wave moves through a medium, the particles of the medium: a) vibrate in a path parallel to the path of the wave b) vibrate in a path perpendicular to the p

Explain electric current, Electric Current: Electric current may be des...

Electric Current: Electric current may be described as the rate of flow of charge. I=q/T Where, I = electric current q = charge T = time The unit of current i

Estimate the power, An engineer is making an estimate for a home owner. Thi...

An engineer is making an estimate for a home owner. This owner has a small stream (Q = 1.4 cfs, T = 40°F) that is located at an elevation H = 34 ft above the owner's residence. The

Calculate the gradient of the function, A scalar function is given by f(x, ...

A scalar function is given by f(x, y, z) = 2xy 2 + xyz 3 . Calculate the gradient of the function at the point (1, 1, 1).

Conducting materials, A copper wire whose diameter is 0.16 cm carries a ste...

A copper wire whose diameter is 0.16 cm carries a steady current of 10 A. What is the current density of the wire?Also calculate the drift velocity of the electrons in copper.

What kinetic energy does it collide into the other sphere, Two faultlessly ...

Two faultlessly conducting spheres are in an evacuated region of space. One is at a potential of -1200 volts as well as the other is at a potential of 1500 volts. A free electron i

Numerical on newton''s ring experiment, Q. I n a Newton's ring experiment,...

Q. I n a Newton's ring experiment, the wavelength of the light used is 6 × 10 -5 cm and the difference of square of diameters of successive rings are 0.125 cm 3 . What will h

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages