Measurements of Landau-level crossings and extended states in magnetic two-dimensional electron gases

R. Knobel, Nitin Samarth, J. G.E. Harris, D. D. Awschalom

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

We present longitudinal and Hall magnetoresistance measurements of a "magnetic" two-dimensional electron gas formed in modulation-doped Zn1-x-yCdxMnySe quantum wells. The electron spin splitting is temperature and magnetic field dependent, resulting in striking features as Landau levels of opposite spin cross near the Fermi level. Magnetization/measurements on the same sample probe the total density of states and Fermi energy, allowing us to fit the transport data using a model involving extended states centered at each Landau level and two-channel conduction for spin-up and spin-down electrons. A mapping of the extended states over the whole quantum Hall effect regime shows no floating of extended states within experimental resolution as Landau levels cross near the Fermi level.

Original languageEnglish (US)
Article number235327
Pages (from-to)2353271-2353278
Number of pages8
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume65
Issue number23
DOIs
StatePublished - Jun 15 2002

Fingerprint

Two dimensional electron gas
Fermi level
electron gas
Quantum Hall effect
Electrons
Magnetoresistance
Semiconductor quantum wells
Magnetization
Temperature distribution
Modulation
Magnetic fields
quantum Hall effect
electron spin
floating
temperature distribution
quantum wells
modulation
conduction
magnetization
probes

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

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Measurements of Landau-level crossings and extended states in magnetic two-dimensional electron gases. / Knobel, R.; Samarth, Nitin; Harris, J. G.E.; Awschalom, D. D.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 65, No. 23, 235327, 15.06.2002, p. 2353271-2353278.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Measurements of Landau-level crossings and extended states in magnetic two-dimensional electron gases

AU - Knobel, R.

AU - Samarth, Nitin

AU - Harris, J. G.E.

AU - Awschalom, D. D.

PY - 2002/6/15

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AB - We present longitudinal and Hall magnetoresistance measurements of a "magnetic" two-dimensional electron gas formed in modulation-doped Zn1-x-yCdxMnySe quantum wells. The electron spin splitting is temperature and magnetic field dependent, resulting in striking features as Landau levels of opposite spin cross near the Fermi level. Magnetization/measurements on the same sample probe the total density of states and Fermi energy, allowing us to fit the transport data using a model involving extended states centered at each Landau level and two-channel conduction for spin-up and spin-down electrons. A mapping of the extended states over the whole quantum Hall effect regime shows no floating of extended states within experimental resolution as Landau levels cross near the Fermi level.

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