Carrier Concentration and Mobility. Effective Mass

Charge Carrier Concentration and Mobility. Effective Mass 

If the reduced conductivity in p-type EuSe obtained by annealing of Eu-rich EuSe is assumed to be due to a decrease in the carrier concentration, then these p-type samples have charge carrier concentrations nc = 10 ° to lO cm at 300 K, Yamada etal. [6]. 

Thermoelectric power (a) measurements on slightly Eu-rich as-grown samples down to 7 K indicate that changes in the conductivity as a function of temperature and magnetic field above lOkOe are mainly caused by changes in the mobility, whereas the conductivity minimum and the negative magnetoresistance at H 10 kOe at temperatures below 20 K are 

The Hall mobility in slightly Eu-rich EuSe at 4.2 and 3.1 K as a function of magnetic field has a broad minimum around 55 K( i 10 and 2x10 cm -V S at3.1 and4.2 K, respectively) and is at both 25 and 100 kOe ca. half an order of magnitude larger [15]. At 4.2 K and 100 kOe Eu-richer samples had mobilities ranging from 35 to 121 cm --s [8]. 

Effective Mass. Microwave permittivity gives m = 0.28 mo, Kuivalainen etal. [9], as compared to m ) =0.36 mo at the bottom of the conduction band from band calculations, Cho [2]. 

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