Effect of localized B and N states on the magneto‐transport of (B,Ga,In)As and (Ga,In)(N,As)

Teubert, J.; Klar, Peter J.; Heimbrodt, W.; Gottschalch, V.; Lindsay, Andrew J.; O’Reilly, Eoin P.

doi:10.1002/pssb.200672540

Cited by 10 publications

(4 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The recently measured electron mobility of 800 cm 2 ͑V s͒ −1 in a BInGaAs sample at ambient pressure 8 is intermediate between that of a conventional alloy and the very low values ͓of order of 100-300 cm 2 ͑V s͒ −1 ͔ observed in GaNAs alloys, 9 with the measured mobility in the BGaAs case decreasing rapidly with increasing hydrostatic pressure to ϳ100 cm 2 ͑V s͒ −1 at 14 kbar, similar to the observed values in GaNAs. 8 Hence, the electronic properties of BGaAs are intermediate between those of conventional and extreme alloys, with some of the measured properties as expected for conventional alloys, while others resemble more closely those of an extreme alloy.…”

Section: Introductionmentioning

confidence: 80%

Theory of conduction band dispersion in diluteBxGa1−xAsalloys

Lindsay¹,

O’Reilly²

2007

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

The conduction band structure of B x Ga 1−x As has a near-linear blueshift of the energy gap, which can be described using the virtual crystal approximation, but a dramatic increase in the band edge effective mass m e * at low B composition, similar to that observed in GaN x As 1−x . We use a tight-binding model to show that isolated B atoms have little effect either on the band gap or lowest conduction band dispersion in B x Ga 1−x As. In contrast, B pairs and clusters introduce defect levels close to the conduction band edge, which, through a weak band-anticrossing interaction, significantly reduce the band dispersion in and around the ⌫ point, thus accounting for the strong increase in m e * and reduction in mobility observed in these alloys.

show abstract

Section: Introductionmentioning

confidence: 80%

Theory of conduction band dispersion in diluteBxGa1−xAsalloys

Lindsay¹,

O’Reilly²

2007

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, recent experiments on B 0.03 In 0.06 Ga 0.91 As using far-infrared magnetooptic ellipsometry, have shown a 44% increase in electron effective mass over that expected for In 0.06 Ga 0.94 As [6], with a further increase in mass measured with increasing carrier concentration. The recently measured electron mobility of 800 cm 2 (Vs) −1 in a BInGaAs sample at ambient pressure [7] is intermediate between that of a conventional alloy and the very low values observed in GaNAs alloys [8], with the measured mobility in the BGaAs case decreasing rapidly with pressure to ∼100 cm 2 (Vs) −1 at 14 kbar, similar to the observed values in GaNAs [7]. Hence some of the electronic properties of BGaAs are as ex- pected for conventional alloys, while others resemble more closely those of an extreme alloy.…”

mentioning

confidence: 99%

Theory of electronic structure of BGaAs and related alloys

Lindsay¹,

O’Reilly

2008

Phys. Status Solidi (c)

Self Cite

View full text Add to dashboard Cite

Previous experiments on Bx Ga1–x As containing a few percent boron show a dramatic increase in electron effective mass, m*e , similar to that observed in many GaNx As1–x samples. By contrast, there is a near‐linear blue‐shift of the energy gap, which can be conventionally described using the virtual crystal approximation. We use a tight‐binding model to show that isolated B atoms have little effect either on the band gap or lowest conduction band dispersion in Bx Ga1–x As. By contrast, B pairs and clusters introduce defect levels close to the conduction band edge (CBE) which, through a weak band‐anticrossing (BAC) interaction, significantly reduce the band dispersion in and around the Γ ‐point, thus accounting for the strong increase in m*e and reduction in mobility observed in these alloys. Calculations show that replacing gallium by aluminium shifts the CBE upwards, leading to a large density of B‐related states in the energy gap. By contrast, indium shifts the band edge downwards, leading eventually to a band edge m*e close to that predicted by the virtual crystal approximation. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

“…a small negative contribution to the MR at low temperatures (up tp -3% at 1.6 K) and a normal positive contribution leading to a small positive MR of 2% at 10 T for T = 1.6 K. At the lowest temperatures an onset of Shubnikov-de-Haas oscillations can be seen. The negative magnetoresistance in this sample can be easily interpreted in the framework of weak-Anderson-localization considering the situation of slightly disturbed band transport [5]. The negative MR effect decreases with increasing temperature and vanishes at around 90 K. The observation of weak-Anderson-localization corresponds well to the metallic temperature dependence of the resistivity (Fig.…”

Section: Resultsmentioning

confidence: 68%

Metal insulator transition in n‐BGaInAs

Teubert

Klar

Heimbrodt

2008

Phys. Status Solidi (c)

Self Cite

View full text Add to dashboard Cite

Isovalent boron is expected to form highly localized states within the conduction band of the GaInAs host which according to most present experimental findings only weakly influences the structure of the extended host states. Here we present magnetotransport (MR) measurements on three n‐type BGaInAs samples doped with silicon which vary in free carrier concentration n from 4.0 × 1016 cm−3 to 7.2 × 1017 cm−3. The three samples differ strongly in their resistivity behaviour. Whereas the sample with the highest n shows metallic behaviour, the transport behaviour of the sample with the lowest n is dominated by hopping transport. The latter is manifested by an exponential increase of the resistivity in the magnetic field. The experimental results are interpreted as a metal insulator transition (MIT). The MIT is found at unexpectedly high carrier concentration compared to GaAs which is attributed to increased alloy disorder in the quarternary alloy mainly due to the localized boron states. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

Effect of localized B and N states on the magneto‐transport of (B,Ga,In)As and (Ga,In)(N,As)

Cited by 10 publications

References 10 publications

Theory of conduction band dispersion in diluteBxGa1−xAsalloys

Theory of conduction band dispersion in diluteBxGa1−xAsalloys

Theory of electronic structure of BGaAs and related alloys

Metal insulator transition in n‐BGaInAs

Contact Info

Product

Resources

About