Detection of Spin Dependent Scattering at High Magnetic Fields

Neutral donor spin-dependent scattering of conduction electrons in silicon field-effect transistors can be used as a spin-state readout mechanism for donor qubits in silicon[1]. Experimentally, the effect is measured by electrically detected magnetic resonance, usually in a low magnetic field regime ($\approx0.35T$)[2]. In such measurements, the resonance signal amplitude is limited by the conduction electron spin polarization, which is typically less than 5\% at those fields. We report recent progress in the measurement of spin-dependent scattering at high magnetic fields ($3.5T-11T$), where the conduction electron polarization is much higher and results in much stronger resonance signals. \newline [1] Sarovar et al, PRB, 78, 245302 (2008), de Sousa et al, PRB,80, 045320 (2009) \newline [2] Lo et al, APL, 91, 242106 (2007)