Spin splitting of upper electron subbands in a SiO2/Si(100)/SiO2 quantum well with in-plane magnetic field.

We observe a lifting of the twofold spin degeneracy of conduction-band electrons in an upper-valley subband with in-plane magnetic field in a SiO₂/Si(100)/SiO₂ quantum well, which is manifest in a splitting of a feature in the conductivity accompanying the occupation of the upper-valley subband. The splitting increases in proportion to the in-plane magnetic field, allowing the product of the effective g-factor and effective mass g^*m^* to be obtained. The value remains constant over wide ranges of valley splitting, total electron density, and potential bias. [ABSTRACT FROM AUTHOR]