Recent content by chenhon5

Hi, thank you very much for your reply. i am looking for some material can be deposited using ebeam evaporation or atomic layer deposition, since very thin layer (~30 nm) is needed.

Hi, Does anyone know which insulator will have very high dielectric strength at room temperature? The dielectric strength is the electric filed strength of a material can resist before it breakdown.

Hi, I have some question about the full well capacity and dynamic range of the CCD camera. The following link lists some full well capacity and dynamic ragnes of some CCD cameras: http://www.andor.com/learning/digital_cameras/?docid=321 My question is how they obtain the electron numbers...

Is anybody knows what kind of equipment or lens can be used to change the direction of the polarization of the laser light (electrical field and magnetic field, but not the direction of the light)? Thanks.

Thank you for your reply. As I know the energy due to the temperature is k*T=0.0259eV, however, the bandgap of InSb is about 0.17eV, which is much larger than the thermal noise. Do you mean even the bandgap of InSb is larger than the thermal noise, but their values are more closed than other...

Is anybody can give me a detailed explanation or reference why the small bandgap IR detectors (eg. InSb photodetecotr) need to work in the cryogenic temperature? In addition, anybody knows what is carrier capture time? Since some article said the photodetector detectivity is proportional to...

Thank you very much. Your explanation is excellent!

Just one more question. Whether the quantum contact conductance comes from two contacts or only one contact? As you mentioned, the wavefunction is "constricted" in the transverse direction when electron flow from big pad to the nano-channel (say from the left pad to the channel). Therefore...

Thank you so much for your replay. You answer is very helpful. But I do not know that much about waveguide. Could you give me more explanation about the waveguide? 1. Whether the contacts or the channel is the waveguide? 2. What is the "mode" you are talking about in this case? Relate to...

I think I made a mistake and misunderstood something. And Bob give me a very clear and good explanation. Electron mostly transport in the surface with high frequency AC, not in all cases. Thanks a lot, Bob.

Say we have a solid wire made of Cu. It seems most electrons transport at the surface of the wire. Right? So is there any difference of the resistance if we have a hollow Cu wire (same diameter with the solid wire). I think the answer shoule be "yes". Right? Becasuse, the resistance R=p*L/A (p...

My question is how the maximum quantum contact conductance 2*q^2/h comes from. The maximum contact conductance can only be obtained when there is no scattering in the contacts between nano-channel and two big pads. (To my understanding, resistance comes from scattering, but if there is no...

Thanks a lot, Don. So do you agree that the Fermi level of semiconductor will be shifted with light illumination in order to generate the Voc?

Yes, I agree. The curves 9 show the IV curves with photoresponse with different light power density. As we know, the Isc is proportional to P (power density), however, the Voc is proportiaon to log(P), therefore...

Thank you for you two's reply. It seems I did misunderstand something. Say we did not apply any bias and light on a Shottky barrier based photodiode, the work function of the metal and Fermi level of the semiconductor will align. So there is not any voltage potential (Voc) created. (I mix it...