Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.751005
Title: Studies relating to cyclotron emission from semiconductors
Author: Cowan, David A.
Awarding Body: University of St Andrews
Current Institution: University of St Andrews
Date of Award: 1985
Availability of Full Text:
Access from EThOS:
Access from Institution:
Abstract:
In this thesis studies relating to cyclotron emission in GaAs, InSb, InP and CdxHg1- xTe (C.M.T.) are described. The effect of the electric field bias on the emission intensity and linewidth in GaAs and InP is studied and a theoretical model is proposed. The study indicates the importance of nonparabolicity and polar mode scattering in determining the intensity and linewidth in these materials. Inter-excited state transitions are observed for the first time in emission- Nonparabolicity splitting is observed in InP and that in GaAs, originally observed in by Gornik (1983),is confirmed. The application of hydrostatic pressure to InSb is observed to narrow the emission line by a factor of three. In experiments on the magnetoimpurity effect in GaAs transitions between the 1S and 2P_, 2P0, 3D-2 and 3D-1 impurity states are observed and central cell structure is observed for the first time. In bulk C.M.T. cyclotron resonance is studied as a function of hydrostatic pressure and reasonable agreement is achieved with accepted values for the variation of band gap with pressure. In the surface layer cyclotron resonance is observed as are Shubnikov de Haas oscillations and electric subband energies are calculated for each of these experiments. Finally the use of cyclotron emission as a spectroscopic source is demonstrated and future developments discussed.
Supervisor: Stradling, R. A. Sponsor: Science and Engineering Research Council (SERC)
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.751005  DOI: Not available
Keywords: QC612.S4C7 ; Semiconductors
Share: