Single Spin Measurement using Single Electron Transistors to Probe Two Electron Systems

We present a method for measuring single spins embedded in a solid by probing two electron systems with a single electron transistor (SET). Restrictions imposed by the Pauli Principle on allowed two electron states mean that the spin state of such systems has a profound impact on the orbital states (positions) of the electrons, a parameter which SET's are extremely well suited to measure. We focus on a particular system capable of being fabricated with current technology: a Te double donor in Si adjacent to a Si/SiO2 interface and lying directly beneath the SET island electrode, and we outline a measurement strategy capable of resolving single electron and nuclear spins in this system. We discuss the limitations of the measurement imposed by spin scattering arising from fluctuations emanating from the SET and from lattice phonons. We conclude that measurement of single spins, a necessary requirement for several proposed quantum computer architectures, is feasible in Si using this strategy.Comment: 22 Pages, 8 Figures; revised version contains updated references and small textual changes. Submitted to Phys. Rev.

A transient capacitance-voltage method for characterizing DX centres

10.1088/0268-1242/11/12/004Semiconductor Science and Technology11121787-1790SSTE

ORGANOMETALLIC EPITAXIAL GROWTH OF GaAs1-xPx

Nous présentons la croissance de GaAS1-xPx utilisant (CH3) 3Ga, AsH3 et PH3. La qualité des couches épitaxiales est évaluée à partir d'analyses en microscopie électronique à balayage et de caractérisation optique. Une étude systématique des variations de taux d'incorporation des éléments V (As et P) a été menée. A partir d'un modèle simple d'incorporation, une énergie d'activation EA ≈ 1 eV est déduite du rapport P/As dans le solide. Ce résultat est discuté sur la base de réactions dans la phase vapeur et de processus adsorption/désorption à l'interface vapeur-solide.Successful epitaxial growth of GaAs1-xPx using (CH3) 3Ga, AsH3 and PH3 is reported. The epitaxial Layer quality is evaluated from SEM analysis and from optical data. A systematic study of variations in the incorporation rates of the group V atoms (As and P) with growth parameters is presented. From a simple model for the incorporation, an activation energy EA≈1.0 eV is deduced for the P/As mixture in the solid. This result is discussed in tenns of vapour phase reactions and adsorption/desorption processes at the vapour-solid interface