Per page discussions (new threads)

Ionic Crystals

Tue, 05 May 2009 05:29:39 +0000

Thanks for give extensive theory about ionic crystal. ;-) It seems that it plays an important role in the development of solid state physics. Does it has any practical application in the life?

Polarization of Materials

Sun, 03 May 2009 18:47:40 +0000

Hi, yuan, you can probably talk more about the application, I mean, the application of polarization in various field except solid oxide fuel cell. For example. it can be used in Liquid Crystal Display(LCD). For LCD, it is composed of two polarizers that transmit light in perpendicular directions, a mirrored surface and a layer of liquid crystal material that is sandwiched between two electrically conducting glass plates.

Ferromagnetic materials

Thu, 30 Apr 2009 18:13:41 +0000

Hi, Jialan,

Very interesting work! And I am curious about the domain structure for ferromagnetic materials. For the polarization of ferroelectric materials, the polarization propagate through a "domain wall motion" mechanism. Does ferromagnetic materials have this property?

Direction & Electric Field Dependence of Dielectric Constant

Thu, 30 Apr 2009 17:56:21 +0000

Hi, Fangxiao:

Good job!

The anisotropic property of ferroelectric materials really influence many aspects of its electric properties. Considering it may show more actual results in reality . Now I have several questions. First, could you tell me again why it is called dielectric constant in history? Also, could you give me some more details about the relations between the dielectric constant and the dipole moment?

Thank you.

transition metal catalysis

Wed, 29 Apr 2009 14:09:29 +0000

Great work.
You can probably list some recent catalyst people are working on.

MOSFETs, and classical and quantum mechanical approaches in MOS characterization

Wed, 29 Apr 2009 13:24:11 +0000

Website will be completed soon. For the MOSFET background, please see Maria's webpage on p-n junctions, MOSFETs and HEMTs. Dharma also gives how work functions of semiconductor and metal (or degenerately doped poly-silicon) are engineered to achieved the desired MOSFET operation.

Gokhan.

Thermoelectricity

Tue, 28 Apr 2009 22:14:00 +0000

What materials are being used to produce thermal electricity. What is efficiency of conversion?

Principles and Applications of Laser

Tue, 28 Apr 2009 17:42:41 +0000

Nice page,

I have read a few papers where they utilize excimer and YAG lasers, and one thing i have notice that these lasers are pulsed (~ns) instead of running them continuously (researchers were trying to melt silicon with them). My question is: are these small time scales limitation of the lasers or are they trying trying to avoid dumping too much power?

Thanks.

Magnetism-Iron Oxide Magnetite

Tue, 28 Apr 2009 16:15:57 +0000

Hey,

I am trying to figure out how to insert the video so you can use it. Right now wikidot only gives directions on how to embed a video from another site, and nothing about inserting a self-made video…..kind of annoying, but I am waiting to hear back from support. In the meantime, I have two videos to choose from, one is a cluster of particles spinning around, and another is a single particle, which would you prefer?

-Vin

Dye-sensitized Solar cell (DSSC)

Tue, 28 Apr 2009 15:52:57 +0000

Now a days people are growing TiO₂ nano-wire which effectively separates electron and hole can you discuss it more.

Solar Cells

Sun, 26 Apr 2009 15:44:02 +0000

nice work kuoting,
what are suitable materials for solar cells, i mean, what is the band gap where there is high efficiency of conversion. (helps us in answering question 2 in homework 3)

Ferroelectrics

Mon, 20 Apr 2009 20:02:57 +0000

Good work BB.
Just curious to know, is it because of polarization in the materials we see ferroelectric behavior or because the material is ferroelectric it gets polarized.

Doped semiconductors in electronic devices & main principles for the operation of transistors

Fri, 17 Apr 2009 15:42:19 +0000

good job Maria. I have cited your work in my term paper on work function.
Its good that you mentioned the carrier density is small and only a very small reverse saturation current flows in (P negative with respect to N) reverse bias and in forward bias (P positive with respect to N) the carrier density is large (it varies exponentially with the applied bias voltage), making the junction conductive and allowing a large forward current. I think, this will get a complete picture if you show an I-V plot like the below one to show these effects.

Magnetocaloric Effect

Thu, 16 Apr 2009 19:40:36 +0000

Good job.

Can you elaborate on how is it possible to transport solid materials from heat to sink as required in cooling cycle of any cooling mechanism.

Lattice Vibrations

Wed, 18 Mar 2009 00:45:59 +0000

hey Yamalia….nice work!….So the number of distinct or indepenent lattice waves, with different wave functions in a crystal is not infinite but depends on the number of atoms N. My understanding is that each mode or state of lattice vibration is an independent lattice vibration and the energy can be increased or decreased by only the quantum amount of 'hw'. And since the mode values inside and outside the range of -(3.14)/a and (3.14)/a are the same then the maximum number of modes is N. And for a 3-D crystal the number of modes is 3N. So I dont know if you want to get a little more into finding vibration modes, but overall nice job.

Examination of a Particle in an Infinite and Finite Potential Well

Tue, 17 Mar 2009 13:44:36 +0000

Good job Leah. You have shown the wavefunctions and probability density functions for several states in the case of particle in a box with infinite potential well. It would be great if you also show them for finite potential well (i.e., both wave functions and probability density functions for several states in one figure)
I am just curious to know how the wave functions look like in a 2-D box and a 3-D box. I know, solving those will be very complicated.