InGaAs/GaAsSb based two-dimensional electron gases

Abstract

Large spontaneous spin splitting in gate-controlled two-dimensional electron gases at normal In 0.75 Ga 0.25 As/In 0.75 Al 0.25 As heterojunctionsThe authors report on two-dimensional electron gases realized in the In 0.53 Ga 0.47 As/GaAs 0.51 Sb 0.49 material system. For different doping levels, the sheet carrier densities were measured to be between 8.4. Â 10 10 and 8.3 Â 10 11 cm À2 . A maximum electron mobility of 42 700 cm 2 /V s was observed at a temperature of 60 K. In addition to alloy scattering, remote ionized impurity scattering is a limiting factor for this material combination, as the GaAs 0.51 Sb 0.49 barriers have the same low effective mass as the In 0.53 Ga 0.47 As channel and therefore allow the wavefunction to protrude into the barrier more than in other established material systems. Angle resolved Hall measurements revealed a strong influence of the crystallographic directions on the carrier mobility and two-dimensional electron population. An additional feature of these two-dimensional electron systems, originating from the fact that In 0.53 Ga 0.47 As and GaAs 0.51 Sb 0.49 show a type-II band alignment and comparable bandgap energies, is spin splitting, due to the Rashba effect, with a Rashba-parameter of 0.42 eVÅ .

Controlling the morphology, composition and crystal structure in gold-seeded GaAs1−xSbxnanowires

“…This alloy is of interest due to its promising applications in high speed optoelectronics, solar cells, infrared photodetectors and even fundamental studies of electron and hole transport when combined into heterostructures with standard III-(As,P) materials. [17][18][19][20][21] Indeed, the bandgap of GaAs 1−x Sb x can be tuned from 870 nm (GaAs) to the near infrared (IR) range (1700 nm for GaSb) and thus has applications in the optical telecommunication industry, near IR light sensing, and thermovoltaics. 22 In addition, it is an advantageous candidate for advanced band structure engineering as it can form a variety of band alignments (type I, II or III) with other common III-V compounds.…”

Accurate Analytical Modeling of Drain Current of Heterojunction Tunneling Field Effect Transistor

“…Although there is no definite value for 𝐸 𝑔,𝑒𝑓𝑓 in the 𝐺𝑎𝐴𝑠 0.5 𝑆𝑏 0.5 /𝐼𝑛 0.53 𝐺𝑎 0.47 𝐴𝑠. Various ranges of effective bandgap can be seen in the literature (30,31). With comparing measured 𝐼 𝐷 − 𝑉 𝐺𝑆 curve for the 𝐺𝑎𝐴𝑠 0.5 𝑆𝑏 0.5 /𝐼𝑛 0.53 𝐺𝑎 0.47 𝐴𝑠 H-TFET, 𝐸 𝑔,𝑒𝑓𝑓 = 0.42𝑒𝑉 is more suitable (31).…”

High electric field transport in GaAs0.51Sb0.49

“…By varying the alloy composition x, one can lattice match this material to a variety of substrates ranging from GaAs, through InP, to InN and InAs. Perhaps it is used most in applications deriving from lattice matching to InP and often incorporating In 0.53 Ga 0.47 As.This has allowed the use of GaAs 0.51 Sb 0.49 to be used in quantum well heterostructures [1][2][3], tunneling devices [4], bipolar transistors [5], field-effect transistors [6,7], backward diodes [8], infrared detectors [9,10], and spin detection [11]. It has also been suggested as a collector in third generation hot carrier solar cells [12].…”