Cyclotron resonance in (GaAs) /(AlAs)  superlattices under ultra-high magnetic fields

Momose, H.; Mori, Nobuya; Hamaguchi, Chihiro; Ikaida, T.; Arimoto, Hideo; Miura, N.

doi:10.1016/s1386-9477(99)00018-1

Cited by 9 publications

(9 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4(b) to reflect the spread of m in this field range. Our measured m at high n are comparable to those reported previously in narrow-well AlAs [11,13]. At low densities, there appears to be some enhancement of m , similar in magnitude to that reported in Si-MOSFETs [5,9]; however, there is a significant spread in the m values that depends on sample and cooldown.…”

Section: And Insupporting

confidence: 89%

“…Based on the saturation of the mobility at high density and the similarity of growth conditions with wider AlAs QWs that exhibit significantly higher mobilities, we surmise that interface-roughness scattering caused by well-width fluctuations is the primary limiting disorder mechanism in our narrow AlAs QW samples. Using the AlAs dielectric constant of 10, and the transverse band effective mass m b 0:21 reported from cyclotron resonance measurements [13], our density range corresponds to 2:8 r s 9:6, where r s is the average interelectron spacing measured in units of the effective Bohr radius. We made measurements down to T 40 mK using lock-in techniques.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Spin Susceptibility of Two-Dimensional Electrons in Narrow AlAs Quantum Wells

et al. 2004

View full text Add to dashboard Cite

We report measurements of the spin susceptibility in dilute two-dimensional electrons confined to a 45 A wide AlAs quantum well. The electrons in this well occupy an out-of-plane conduction-band valley, rendering a system similar to two-dimensional electrons in Si-MOSFETs but with only one valley occupied. We observe an enhancement of the spin susceptibility over the band value that increases as the density is decreased, following closely the prediction of quantum Monte Carlo calculations and continuing at finite values through the metal-insulator transition.

show abstract

Section: And Insupporting

confidence: 89%

mentioning

confidence: 99%

Spin Susceptibility of Two-Dimensional Electrons in Narrow AlAs Quantum Wells

et al. 2004

View full text Add to dashboard Cite

show abstract

“…In bulk AlAs, the effective masses in the transverse and longitudinal directions of the ellipsoid Fermi surface are 0.22m 0 and 0.97m 0 , respectively [24]. For AlAs QWs thinner than 6.0 nm, the 2DES occupies the lower nondegenerate valley, where experiments report a transverse mass of (0.2-0.3)m 0 [25][26][27]. The obtained m ⋆ SL /m 0 , which approaches the expected value (0.2-0.3) with increasing V FG , is reasonable.…”

Section: B Circuit Modelmentioning

confidence: 99%

Screening effects of superlattice doping on the mobility of GaAs two-dimensional electron system revealed by in-situ gate control

Akiho,

Muraki

2021

Preprint

View full text Add to dashboard Cite

We investigate the screening effects of excess electrons in the doped layer on the mobility of a GaAs twodimensional electron system (2DES) with a modern architecture using short-period superlattice (SL) doping. By controlling the density of excess electrons in the SL with a top gate while keeping the 2DES density constant with a back gate, we are able to compare 2DESs with the same density but different degrees of screening using one sample. Using a field-penetration technique and circuit-model analysis, we determine the density of states and excess electron density in the SL, quantities directly linked to the screening capability. The obtained relation between mobility and excess electron density is consistent with the theory taking into account the screening by the excess electrons in the SL. The quantum lifetime determined from Shubnikov-de Haas oscillations is much lower than expected from theory and did not show a discernible change with excess electron density.

show abstract

“…1). The conduction mass, in units of the bare electron mass, is m l = 1.04 along each ellipsoid's major (longitudinal) axis and m t = 0.21 along the minor (transverse) axes [4]. Confining the charges along a crystal direction breaks the bulk valley degeneracy as a consequence of the valleys' mass anisotropy.…”

mentioning

confidence: 99%

High-mobility AlAs quantum wells with out-of-plane valley occupation

Vakili

Shkolnikov

Tutuc

et al. 2006

Applied Physics Letters

View full text Add to dashboard Cite

Employing state-of-the-art molecular beam epitaxy techniques to grow thin, modulation-doped AlAs quantum wells, we have achieved a low temperature mobility of 5.5 m$^2$/Vs with out-of-plane occupation, an order of magnitude improvement over previous studies. However, due to the narrow well width, mobilities are still limited by scattering due to interface roughness disorder. We demonstrate the successful implementation of a novel technique utilizing thermally-induced, biaxial, tensile strain that forces electrons to occupy the out-of-plane valley in thicker quantum wells, reducing interface roughness scattering and allowing us to achieve mobilities as high as 8.8 m$^2$/Vs.Comment: 3 pages, 3 figures, submitted for publicatio

show abstract

Cyclotron resonance in (GaAs) /(AlAs) superlattices under ultra-high magnetic fields

Cited by 9 publications

References 17 publications

Spin Susceptibility of Two-Dimensional Electrons in Narrow AlAs Quantum Wells

Spin Susceptibility of Two-Dimensional Electrons in Narrow AlAs Quantum Wells

Screening effects of superlattice doping on the mobility of GaAs two-dimensional electron system revealed by in-situ gate control

High-mobility AlAs quantum wells with out-of-plane valley occupation

Contact Info

Product

Resources

About