Volume dependence of the electronic dielectric constant of crystals under hydrostatic pressure

1978 ◽  
Vol 18 (12) ◽  
pp. 7186-7188 ◽  
Author(s):  
Jai Shanker ◽  
A. K. G. Lashkari ◽  
O. P. Sharma
2007 ◽  
Vol 21 (16) ◽  
pp. 2735-2747 ◽  
Author(s):  
G. J. ZHAO ◽  
X. X. LIANG ◽  
S. L. BAN

The binding energies of excitons in finite barrier quantum wells under hydrostatic pressure are calculated by a variational method. The influences of hydrostatic pressure on the effective masses of the electron and hole, the dielectric constant, and the conduction band offset between the well and barriers are taken into account in the calculation. The numerical results for the GaAs/Al x Ga 1-x As and GaN/Al x Ga 1-x N quantum wells are given respectively. It is shown that the exciton binding energy increases linearly with the pressure and the pressure effect on arsenide quantum wells is more obvious than that on nitride ones. The exciton binding energies monotonically increase with increasing barrier height, which is related to the Al concentration of the barriers and the influence of the pressure.


1978 ◽  
Vol 21 (85) ◽  
pp. 161-172 ◽  
Author(s):  
M. Hubmann

Abstract This paper describes measurements of the dielectric constant and of the conductivity on pure and doped ice single crystals subjected to hydrostatic pressure. The dopants used were NH3 (c NH3 ≈ 5 × 10-5 to 1.2 × 10-4 mol/1) or HF (c HF = 5 × 10-6 and 5 × 10-4 mol/1). The pressure and temperature ranges covered were 1 to 1 500 bar and — 15 to 60°C. The activation volumes for the orientational and the ionic contribution to the conductivity could be determined. A definitive interpretation is not possible because many questions concerning the formation of the defects are still open, hi addition to the main subject, some new data from conductivity measurements on NH3-doped single crystals at atmospheric pressure are presented.


1977 ◽  
Vol 15 (4) ◽  
pp. 2363-2365 ◽  
Author(s):  
H. P. Sharma ◽  
Ram Niwas ◽  
Jai Shanker ◽  
M. P. Verma

Sign in / Sign up

Export Citation Format

Share Document