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

What do you mean by alloy, Q. Explain an alloy? Answer:- An alloy ...

Q. Explain an alloy? Answer:- An alloy is a homogeneous hybrid of two or else more elements at least one of which is a metal and where the resulting material has metallic

What do you mean by a zener diode, Illustrate the operation of NOT gate an...

Illustrate the operation of NOT gate and also provide its truth table. What do you mean by a Zener diode? Illustrate how it is used as voltage regulator.

Work, a catapult can hurl a rock straight up in the air 45 m high. What is...

a catapult can hurl a rock straight up in the air 45 m high. What is the maximun range of the catapult?

Measure the distance from the sun for new planet, Assume a new planet was d...

Assume a new planet was discovered to orbit the Sun with a period 5 times that of Pluto. Using the data, measure the average distance from the Sun for this new planet.

Write any four characteristics of electromagnetic waves, Write any four cha...

Write any four characteristics of electromagnetic waves. Give two uses each of 1. Radio-waves 2. Micro-waves.

What are quarter wave plates, What are a quarter wave plates? Get the expre...

What are a quarter wave plates? Get the expressions for its thickness in terms of refractive indices for E-ray, O-ray and wavelength?

Plot the v-t graph showing the entire motion of the dragster, A dragster be...

A dragster begins from rest and accelerates for 4.0 s at a rate of 5.0 m/s2. It then travels at a constant speed for 2.5 s. A parachute opens, stopping the vehicle at a constant ra

How cph takes spin and converts to graviton, How CPH takes spin and convert...

How CPH takes spin and converts to graviton? Answer- A CPH Principle says a CPH moves with constant speed as Vc, Vc>c in any inertial frame and any space, therefore that

Find the electric potential, Q. Find the electric potential at a distance 0...

Q. Find the electric potential at a distance 0.09 m from a charge of 4 X 10 -7 C. The electric potential V = ( 1/4πεo ) q /r = ( 9 X 10 9 X 4 X 10 -7 )/ 9 X 10 -2 = 4 X 10

Microwave, Write an assembly program to make a microwave. Need: 1. T...

Write an assembly program to make a microwave. Need: 1. The microwave has a clock (hh:mm:ss am/pm) and the user should be able to alter the clock at any time. 2. For c

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages