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Title: Tuning spin dynamics and localization near the metal-insulator transition in Fe/GaAs heterostructures

Journal Article · · Physical Review B
 [1];  [2];  [3];  [4];  [2];  [1]
  1. The Ohio State Univ., Columbus, OH (United States)
  2. Univ. of Iowa, Iowa City, IA (United States)
  3. Univ. of California, Riverside, CA (United States)
  4. The Ohio State Univ., Columbus, OH (United States); Univ. of California, Riverside, CA (United States)
+ Show Author Affiliations

We present a simultaneous investigation of coherent spin dynamics in both localized and itinerant carriers in Fe/GaAs heterostructures using ultrafast and spin-resolved pump-probe spectroscopy. We find that for excitation densities that push the transient Fermi energy of photocarriers above the mobility edge there exist two distinct precession frequencies in the observed spin dynamics, allowing us to simultaneously monitor both localized and itinerant states. For low magnetic fields (below 3.00 T) the beat frequency between these two excitations evolves linearly, indicating that the nuclear polarization is saturated almost immediately and that the hyperfine coupling to these two states is comparable, despite the 20 times enhancement in nuclear polarization provided by the presence of the Fe layer. At higher magnetic fields (above 3.00 T) the Zeeman energy drives reentrant localization of the photocarriers. Subtracting the constant hyperfine contribution from both sets of data allows us to extract the Lande g factor for each state and estimate their energy relative to the bottom of the conduction band, yielding -2.16 and 17 meV for localized and itinerant states, respectively. This work advances our fundamental understanding of spin-spin interactions between electron and nuclear spin species, as well as between localized and itinerant electronic states, and therefore has implications for future work in both spintronics and quantum information/computation.

Research Organization:
The Ohio State Univ., Columbus, OH (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
FG02-03ER46054; SC0001304
OSTI ID:
1480653
Alternate ID(s):
OSTI ID: 1478687
Journal Information:
Physical Review B, Vol. 98, Issue 13; ISSN 2469-9950
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (28)

A silicon-based nuclear spin quantum computer journal May 1998
Graphene spintronics journal October 2014
Electron-spin relaxation in bulk GaAs for doping densities close to the metal-to-insulator transition journal February 2010
A single-atom electron spin qubit in silicon journal September 2012
Electronic measurement and control of spin transport in silicon journal May 2007
Theory of electron spin relaxation in n -doped quantum wells journal February 2010
ESR linewidth behavior for barely metallic n -type silicon journal October 1987
Anisotropic spin relaxation in n -GaAs from strong inhomogeneous hyperfine fields produced by the dynamical polarization of nuclei journal October 2015
Electrical detection of spin transport in lateral ferromagnet–semiconductor devices journal February 2007
Scanning Confocal Optical Microscopy and Magnetic Resonance on Single Defect Centers journal June 1997
Quantum computing with defects journal April 2010
Ferromagnetic Imprinting of Nuclear Spins in Semiconductors journal October 2001
Resonant Spin Amplification in n -Type GaAs journal May 1998
Tuning the dynamic exchange interaction in ferromagnet/semiconductor heterostructures conference September 2015
Coherent Dynamics of Coupled Electron and Nuclear Spin Qubits in Diamond journal October 2006
Electron-nuclei spin coupling in GaAs—Free versus localized electrons journal March 2012
A study of the conduction band non-parabolicity, anisotropy and spin splitting in GaAs and InP journal September 1987
Theory of optical orientation in n -type semiconductors journal September 2004
Electron spin dynamics in cubic GaN journal December 2016
Room temperature coherent control of defect spin qubits in silicon carbide journal November 2011
Spin coherence and dephasing in GaN journal March 2001
Ferromagnetic Resonance Spin Pumping and Electrical Spin Injection in Silicon-Based Metal-Oxide-Semiconductor Heterostructures journal December 2015
Manipulation of Spin Transport in Graphene by Surface Chemical Doping journal May 2010
All-Optical Magnetic Resonance in Semiconductors journal January 2000
Inversion of Ferromagnetic Proximity Polarization by MgO Interlayers journal June 2008
Spontaneous spin coherence in n -GaAs produced by ferromagnetic proximity polarization journal March 2002
Exchange-Driven Spin Relaxation in Ferromagnet-Oxide-Semiconductor Heterostructures journal March 2016
Fabrication of sub-transistor via holes for small and efficient power amplifiers using highly selective GaAs∕InGaP wet etching
  • Uchiyama, Hiroyuki; Ohta, Hiroshi; Shiota, Takashi
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 24, Issue 2 https://doi.org/10.1116/1.2178368
journal January 2006

Figures / Tables (4)

FIG. 1(p. 17)figure FIG. 1
FIG. 2(p. 18)figure FIG. 2
FIG. 3(p. 19)figure FIG. 3
FIG. 4(p. 20)figure FIG. 4

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Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
Spin
spintronics
magnetism
semiconductor
hyperfine
coherent
ultrafast