The Density of States

Semiconductor Optoelectronics by Prof. M. R. Shenoy, Department of Physics, IIT Delhi. For more details on NPTEL visit nptel.iitm.ac.in

[@b.k.kashyap3623]

prof. Shenoy is still teaching(Optical Electronics) at iit Delhi & We had a quiz last week😃.

[@anmoltiwari233]

The intro is like we going to watch a video of TOM & JERRY

[@Eshi6767]

This is so funny

[@aks6657]

,🤣🤣🤣🤣

[@sanskarkumar6484]

😂😂

[@thetrend000]

😂😂

[@selvanambi6279]

Mexicano by luis cobos Royal Philharmonic

[@halilibrahimcetin9448]

Hi, i'm a student at Bosphorus University Istanbul. Your lectures on semiconductors are 1000x better than our incompetent lecturer could you consider lecturing at my university? Thank you😂 The way he is conveying the topic is adorable.

[@MuhammadAli-px1ob]

He definitely is an awesome teacher! This is one of the best lectures i have seen!

[@miguelaphan58]

from venezuela, exelente edition..wonderfull teachers.....no doubts, the next first super power INDIA....

[@curiousbit9228]

This professor is Brilliant and very calm!! I love him and his style!!

[@CombustingRatsEH]

Hi, i'm a student at imperial college london. Your lectures on semiconductors are 1000x better than our incompetent lecturer could you consider lecturing at my university? Thank you

[@shanmukhsagi9166]

Lolz bro aint easy to just go to London and join as a prof in a college..... Moreover he is more needed in India😁

[@Unexpectedthings007]

Man even icl have incompetent teachers wow

[@GhulamNabiDar]

K TAKES BILLION VALUES AND YOUR LECTURE 100S OF BILLIONS........... ENLIGHTED SIR THANKS

[@satirthapaulshyam7769]

whenever someone told you it is a soln of ... in qm, assume it they have told you it is a soln of schrodinger eqn . Q1:most of my frnds asking me why these carriers are staying near the bottom of the conduction band? Ans:As all electrons try to get least amount of energy as possible to become more stable thats why they occupy the bottom zone of band and as they are small in number so they can easily conjusted themselves in the lower bottom region of conduction band and we can do a parabolic thinking.and at k=0 the p is zero hence the KE =0

[@shashikantmishra4460]

Old is gold❤

[@debabratadey923]

now i understand the motivation behind density of states

[@nihallimbu3250]

Highly informative lecture.

[@newbie8051]

I'm so happy we don't have to remember these derivations and stuff Anyways nice lectures, funny to see random class shots and see everyone get camera conscious

[@curiousbit9228]

Maybe Kx, Ky & Kz are not independent integral multiples if we are dealing with not a plane wave but a spherical wave.

[@MrMarshallAC]

I wish that I had Prof. Shenoy as my faculty in 2004 while I studied this subject.

[@irtizahasan6107]

MrMarshallAC I don't

[@deepakurup2112]

Wonderful lecturer 🙏

[@gauravbassi5871]

proud to be an indian

[@harithakdas5314]

Amazing lecture Thank you soo much sir

[@MrMarshallAC]

The 'k' factor seems similar to the propagation constant in a rectangular waveguide at resonance. The movement of electrons in a unit crystal cell seems similar to the EM wave propagation in a rectangular wave guide in TE mode.

[@irfanali-kw5yy]

really amazing sir

[@gauthambekal235]

Surperb lec Sir!!!

[@hinapatel9129]

Thank you so much for this wonderful explanation. I have one doubt that When electron is inside the semiconductor, it will move under the influence of external or internal field?

[@vinaysiwach9734]

they move under extenrnal force , only when yu consider mass of electron as effective mass ,

[@vinaysiwach9734]

we use effective mass to isolate electron from internal environment (ie . internal force )

[@quantaali543]

13:28 lol btw, amazing lecture......

[@Paivren]

Good lecture. However, there is a mistake: kr is NOT always =Npi. This only holds for points r at the boundary.

[@mandlikprajwal466]

No it's always true as your wave function should vanish beyond the lattice

[@priyanshubansal6776]

why they show us the faces of audience in between the lecture

[@shreyashetty372]

Made me to recollect those beautiful memories of Tom and Jerry Those lines I have mentioned in the top are just after watching few seconds of intro...... But the lecture was awesome..... He was teaching a topic that is completely out of world for me...... But even for a second also I never felt that I'm not understanding and its going out of my mind..... May be this is IIT.......

[@untold_cambridge]

Why the lecture number is missing in title. i think KZbin is updated

[@curiousbit9228]

are Kx, Ky & Kz still independent integral multiples if we are dealing with a spherical wave??

[@PhysicsMath]

Spherical wave or spherical shell

[@akanchhakumari5666]

how no. of e in VB is same order as no. of atoms in VB. (though a single atom contain minimum two e)

[@prathamsahil4029]

How is this discussion relevant to designing solar cells?

[@surajitghosh6619]

So at the origin of E K diagram k is not zero? Here k just have minimum value 41:21 ?

[@hassanedds3785]

I can't understand why 2k.r=N.2pi pls someone help me.

[@user-yd1mx3th3u]

me too

[@quantaali543]

Do you agree that there should be integral number of nodes in the standing wave condition? The simple explanation is that when the wave travels from one end to the other and comes back it covers a total angular distance of 2Npi. k.r is the phase, roughly speaking, it is the angular distance covered by the wave in one trip.

[@mandlikprajwal466]

You cannot show the value of k by movement of electron as k is associated with wave nature of electron in qm @39:00

[@amanladdu9664]

sir yeh 3d me h ya koi or dimension me

[@108109093]

Prof. Shenoy says that m, n and p cannot be 0. Is that is the case, how can k=0 (gamma point) ever be realized because for gamma point all three k_x, k_y and k_z must be zero, i.e. essentially m, p and q must be zero? Can someone help! Thanks!

[@artiyadav7879]

Yes ,,,,m,p &q are intergers & can take zero value , its just little mistake did by great professor

[@curiousbit9228]

at gamma point k = 0 not because m, n & p = 0 but because wavelength tends to zero

[@arfatahmad285]

Bro m, p, q can't be simultaneously zero, at least one should be non zero, if this happens then electron will be static inside the crystal which is absurd.

[@shantanusaha6784]

If effective mass is inversely proportional to mobility then how come the electron mobility of Si is greater than the hole mobility? 15:23

[@t_a7923]

I have the same doubt..did you find an answer..please reply..

[@akanchhakumari5666]

@@t_a7923 hole is consider to be slower than electron as movement of holes is based on release and trap mechanism unlike electrons

[@t_a7923]

@@akanchhakumari5666 thankyou

[@mandlikprajwal466]

It will also depend on relaxation time of carrier

[@marcos1289]

00:20

[@ashfaqahmad8340]

what is meant by cc?

[@imphoton]

Cubic centimetre

[@ashfaqahmad8340]

any one let me know ...what is meant by carrierr per cc? cc stand per?

[@Soumya566]

cc is cm cube

[@Oindrih]

24:34 :D