Determination of the liquid-gas phase diagram for electrons and holes in germanium

The existence of the electron-hole gas (EHG) phase has been confirmed in Ge by direct observation and the phase diagram and critical point of the liquid-gas transition have been determined. The position of the metal-insulator transition has been estimated. The electron-hole 1iquid-EHG-exciton system was investigated spectroscopically with particular attention paid to the liquid-gas critica1 region. Theoretical 1ineshapes for the electron-hole liquid (EHL) and excitons are derived and used to determine the liquid density. Measurements of the exciton line second moment and the ratio of the forbidden intensity to the allowed intensity are discussed and used to present convincing evidence that the broadening of the low energy edge of the exciton line near Tc is due to luminescence from the EHG. The lever rule for two coexisting phases is combined with the ratio of the EHG and EHL intensities to determine the EHG density. A universal liquid-gas coexistence curve is fitted to the results and the critical point is found x 1016 3 to lie at Tc = 7.0 ±0.1 K, nc = 8.9 ±O.S cm-. From measurements of the exciton second moments as a function of temperature the position of the metal-insulator transition is estimated.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Year dc:date

2011

Author dc:creator

• Miniscalco, William Joseph

Contributors dc:contributor

• Salamon, Myron B.

• liquid-gas phase diagram
• electron-hole gas (EHG) phase
• germanium
• metal-insulator transition

Statement dc:rights

• 1977 William Joseph Miniscalco

Language dc:language

en

Identifier

252917

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/25629