Fermi dirac level, Electrical Engineering

Assignment Help:

Fermi Dirac level:

Sol. The Fermi level is simply a reference energy level. It is the energy level at which the probability of finding an electron n energy unit above it in the conduction band is equal to the probability of finding a hole n energy units below it in the valence band. Very simply, it can be considered to the average energy level of the electrons, as illustrated in fig. (a). For simplification let us assume that (i) widths of energy bands are  small in comparison to forbidden energy gap between them (ii) all levels in a band have the same energy, bandwidths being assumed to be small (iii) energies of all levels in valence band are E0, as shown in fig. (a) and (iv) energies of all levels in conduction band are EG. Let the zero energy reference level be taken arbitrarily at the top of the valence band, as shown in fig. (b). Now number of electrons in conduction band, where P represents the probability of an electron having energy EG. Its value may be determined from Fermi Dirac probability distribution function given as where P (E) is the probability of finding an electron having any particular value of energy E.


Related Discussions:- Fermi dirac level

Find the voltage at the load terminal, Q. Two three-phase generators are su...

Q. Two three-phase generators are supplying to a common balanced three-phase load of 30 kW at 0.8 power factor lagging. The per-phase impedance of the lines connecting the generato

Balance Business Score Card in KPI, Balance Business Score Card in KPI ...

Balance Business Score Card in KPI Information Age The current era is driven by the information. It is a revolutionary transformation and industries are competing in th

Determine the voltage drop, A 15 volts source is applied to a series 150 mH...

A 15 volts source is applied to a series 150 mH inductor and 169 pF capacitor. The resistance of the inductor plus the connecting wires is 1,6 W. Determine the voltage drop and

Emf produced by windings, Q. emf produced by windings? The time variati...

Q. emf produced by windings? The time variation of emf for a single conductor corresponds to the spatial variation of air-gap flux density. By suitable winding design, the harm

#DSP ., #The requirement is as follows- There is a signal which is in the r...

#The requirement is as follows- There is a signal which is in the range of 0 to 5Hz. This signal frequency composition is to determined. The resolution of the determination is 1Hz.

Computes similarity between two histograms, Write an m-file "distan.m"  whi...

Write an m-file "distan.m"  which does all the following operations: (i) computes 10 dimensional histogram of an input image             h1=sum(hist(imn,10)'); (ii) computes

Embedded system, 10. List the three ways in which an RTOS handles ISRs in a...

10. List the three ways in which an RTOS handles ISRs in a multitasking environment

Determine the input current and input voltage, Q. A 100-kVA, 2300:230-V, 60...

Q. A 100-kVA, 2300:230-V, 60-Hz, single-phase transformer has the following parameters: R 1 = 0.30 , R 2 = 0.003 , RC 1 = 4.5k, X 1 = 0.65 , X 2 = 0.0065 , and Xm 1 = 1.

Determine the electromagnetic torque developed, Q. A dc series motor, with ...

Q. A dc series motor, with a design constant K a = 40 and flux per pole of 46.15 mWb, operates at 200 V while taking a current of 325 A. The total series-field and armature-circui

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd