Valley degeneracies in (111) silicon quantum wells
نویسندگان
چکیده
منابع مشابه
Valley splitting in finite barrier quantum wells
Valley splitting in finite barrier quantum wells" (2008). Birck and NCN Publications. Paper 148. The valley splitting ͑VS͒ in a silicon quantum well is calculated as a function of barrier height with both the multiband sp 3 d 5 s ء model and a simple two-band model. Both models show a strong dependence of the VS on barrier height. For example, in both models some quantum wells exhibit a sharp m...
متن کاملValley splitting in V-shaped quantum wells
The valley splitting senergy difference between the states of the lowest doubletd in strained silicon quantum wells with a V-shaped potential is calculated variationally using a two-band tight-binding model. The approximation is valid for a moderately long sapproximately 5.5–13.5 nmd quantum well with a V-shaped potential which can be produced by a realistic delta-doping on the order of nd<10 c...
متن کاملElectronic thermal conductivity and thermoelectric figure of merit of n-type PbTeÕPb1ÀxEuxTe quantum wells
We have investigated the electronic thermal conductivity and thermoelectric figure of merit of ~100! and ~111! oriented PbTe/Pb12xEuxTe quantum wells. Our theoretical formalism includes the nonparabolicity of the carrier dispersion, band anisotropy, as well as carrier scattering on acoustic and optical phonons and presents a substantial improvement over existing models. The kinetic equations ar...
متن کاملGenetic design of enhanced valley splitting towards a spin qubit in silicon
The long spin coherence time and microelectronics compatibility of Si makes it an attractive material for realizing solid-state qubits. Unfortunately, the orbital (valley) degeneracy of the conduction band of bulk Si makes it difficult to isolate individual two-level spin-1/2 states, limiting their development. This degeneracy is lifted within Si quantum wells clad between Ge-Si alloy barrier l...
متن کاملMeasurement and modeling of ultrafast carrier dynamics and transport in germanium/silicon-germanium quantum wells.
We measure the intervalley scattering time of electrons in the conduction band of Ge quantum wells from the direct Γ valley to the indirect L valley to be ~185 fs using a pump-probe setup at 1570 nm. We relate this to the width of the exciton peak seen in the absorption spectra of this material, and show that these quantum wells could be used as a fast saturable absorber with a saturation fluen...
متن کامل