Change of ε with pressure for Semiconductors

Click For Summary
SUMMARY

The discussion centers on the relationship between the dielectric constants εs and ε∞ of semiconductors, specifically InAs, InP, and InSb, and their dependence on pressure. According to Sado Adachi's book "Properties of Group-IV, III–V and II–VI Semiconductors," both εs and ε∞ decrease linearly with increasing pressure. The effects can be analyzed using Density Functional Theory (DFT) or through empirical measurements that propose fitted functions at equilibrium. The relationship between pressure and the zone center phonon mode frequency ω is suggested to follow the form √p α ω, indicating a complex interaction influenced by non-equilibrium states.

PREREQUISITES
  • Understanding of dielectric constants in semiconductors
  • Familiarity with Density Functional Theory (DFT)
  • Knowledge of phonon modes and their frequencies
  • Basic concepts of thermodynamic forces and their effects on materials
NEXT STEPS
  • Research empirical formulas for pressure dependence of dielectric constants in InAs, InP, and InSb
  • Explore Density Functional Theory (DFT) applications in semiconductor physics
  • Investigate the relationship between pressure and phonon frequencies in semiconductor materials
  • Review scientific literature on non-equilibrium states in semiconductor materials
USEFUL FOR

Researchers in semiconductor physics, materials scientists, and engineers focusing on the optical properties of semiconductor materials under varying pressure conditions.

IWantToLearn
Messages
95
Reaction score
0
In "Sado Adachi" book "Properties of Group-IV, III–V
and II–VI Semiconductors" page 222, he reported that "both εs and ε decrease almost linearly with increasing pressure", however i was not able to find any empirical formula to describe these relationship for materials InAs, InP, InSb, where can i find these relations?
 
Physics news on Phys.org
In general, I would find the effect of material-dependent pressure on the optical properties of materials by two ways.
(i) It can be computed from first principles using Density Functional Theory.
(ii) There are also some experimental measurements which propose some fitted functions for a description at equilibrium, let's say.
In general, the effect of pressure may be a transient effect, which means that non-equilibrium can make you reach a state of matter which was not observed experimentally so far.
Would you have access to scientific literature, maybe? http://scholar.google.com would help here.
 
  • Like
Likes   Reactions: IWantToLearn
εs varies with 1/ω2 , where ω is the zone center phonon mode frequency as you can find in the classic by Born and Huang. Also as you increase the pressure, ω increases because the ions get closer, the bonds get stronger, and the vibrations become faster. I do not think there is a clear-cut formula to describe pressure (p) vs. ω, but according to your statement , it should be something like √p α ω.

I do not fully understand the variation of ε∞ with external thermodynamic forces such as pressure.
 
  • Like
Likes   Reactions: IWantToLearn and MisterX

Similar threads

  • · Replies 0 ·
Replies
0
Views
4K
  • · Replies 19 ·
Replies
19
Views
19K
  • · Replies 15 ·
Replies
15
Views
8K
  • · Replies 5 ·
Replies
5
Views
4K
  • · Replies 13 ·
Replies
13
Views
4K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
Replies
24
Views
8K
  • · Replies 29 ·
Replies
29
Views
11K
  • · Replies 72 ·
3
Replies
72
Views
10K