Random telegraph noise from magnetic nanoclusters in the ferromagnetic semiconductor (Ga,Mn)As

M. Zhu, X. Li, G. Xiang, N. Samarth

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Measurements of the low-frequency electrical noise in the ferromagnetic semiconductor (Ga,Mn)As reveal an enhanced integrated noise at low temperature. For moderate localization, we find a 1/f normalized power spectrum density over the entire range of temperatures studied (4.2 K<T<70 K). However, for stronger localization and a high density of Mn interstitials, we observe Lorentzian noise spectra accompanied by random telegraph noise. Magnetic field dependence and annealing studies suggest that interstitial Mn defects couple with substitutional Mn atoms to form nanoscale magnetic clusters characterized by a net moment of ∼20 μB whose fluctuations modulate hole transport.

Original languageEnglish (US)
Article number201201
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume76
Issue number20
DOIs
StatePublished - Nov 5 2007

Fingerprint

Telegraph
Nanoclusters
nanoclusters
Semiconductor materials
interstitials
Power spectrum
noise spectra
Annealing
Magnetic fields
Atoms
Temperature
Defects
power spectra
low frequencies
moments
annealing
defects
magnetic fields
atoms
temperature

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

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Random telegraph noise from magnetic nanoclusters in the ferromagnetic semiconductor (Ga,Mn)As. / Zhu, M.; Li, X.; Xiang, G.; Samarth, N.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 76, No. 20, 201201, 05.11.2007.

Research output: Contribution to journalArticle

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