Persistent sourcing of coherent spins for multifunctional semiconductor spintronics

I. Malajovich, J. J. Berry, N. Samarth, D. D. Awschalom

Research output: Contribution to journalArticle

207 Citations (Scopus)

Abstract

Recent studies of n-type semiconductors have demonstrated spin-coherent transport over macroscopic distances, with spin-coherence times exceeding 100 ns; such materials are therefore potentially useful building blocks for spin-polarized electronics ('spintronics'). Spin injection into a semiconductor (a necessary step for spin electronics) has proved difficult; the only successful approach involves classical injection of spins from magnetic semiconductors. Other work has shown that optical excitation can provide a short (<500 ps) non-equilibrium burst of coherent spin transfer across a GaAs/ZnSe interface, but less than 10% of the total spin crosses into the ZnSe layer, leaving long-lived spins trapped in the GaAs layer (ref. 9). Here we report a 'persistent' spin-conduction mode in biased semiconductor heterostructures, in which the sourcing of coherent spin transfer lasts at least 1-2 orders of magnitude longer than in unbiased structures. We use time-resolved Kerr spectroscopy to distinguish several parallel channels of interlayer spin-coherent injection. The relative increase in spin-coherent injection is up to 500% in the biased structures, and up to 4,000% when p-n junctions are used to impose a built-in bias. These experiments reveal promising opportunities for multifunctional spin electronic devices (such as spin transistors that combine memory and logic functions), in which the amplitude and phase of the net spin current are controlled by either electrical or magnetic fields.

Original languageEnglish (US)
Pages (from-to)770-772
Number of pages3
JournalNature
Volume411
Issue number6839
DOIs
StatePublished - Jun 14 2001

Fingerprint

Semiconductors
Injections
Magnetic Fields
Spectrum Analysis
Equipment and Supplies
gallium arsenide
Transfer (Psychology)

All Science Journal Classification (ASJC) codes

  • General

Cite this

Malajovich, I. ; Berry, J. J. ; Samarth, N. ; Awschalom, D. D. / Persistent sourcing of coherent spins for multifunctional semiconductor spintronics. In: Nature. 2001 ; Vol. 411, No. 6839. pp. 770-772.
@article{13d1bd42c757459e9d30eeae573ae0f0,
title = "Persistent sourcing of coherent spins for multifunctional semiconductor spintronics",
abstract = "Recent studies of n-type semiconductors have demonstrated spin-coherent transport over macroscopic distances, with spin-coherence times exceeding 100 ns; such materials are therefore potentially useful building blocks for spin-polarized electronics ('spintronics'). Spin injection into a semiconductor (a necessary step for spin electronics) has proved difficult; the only successful approach involves classical injection of spins from magnetic semiconductors. Other work has shown that optical excitation can provide a short (<500 ps) non-equilibrium burst of coherent spin transfer across a GaAs/ZnSe interface, but less than 10{\%} of the total spin crosses into the ZnSe layer, leaving long-lived spins trapped in the GaAs layer (ref. 9). Here we report a 'persistent' spin-conduction mode in biased semiconductor heterostructures, in which the sourcing of coherent spin transfer lasts at least 1-2 orders of magnitude longer than in unbiased structures. We use time-resolved Kerr spectroscopy to distinguish several parallel channels of interlayer spin-coherent injection. The relative increase in spin-coherent injection is up to 500{\%} in the biased structures, and up to 4,000{\%} when p-n junctions are used to impose a built-in bias. These experiments reveal promising opportunities for multifunctional spin electronic devices (such as spin transistors that combine memory and logic functions), in which the amplitude and phase of the net spin current are controlled by either electrical or magnetic fields.",
author = "I. Malajovich and Berry, {J. J.} and N. Samarth and Awschalom, {D. D.}",
year = "2001",
month = "6",
day = "14",
doi = "10.1038/35081014",
language = "English (US)",
volume = "411",
pages = "770--772",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Publishing Group",
number = "6839",

}

Persistent sourcing of coherent spins for multifunctional semiconductor spintronics. / Malajovich, I.; Berry, J. J.; Samarth, N.; Awschalom, D. D.

In: Nature, Vol. 411, No. 6839, 14.06.2001, p. 770-772.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Persistent sourcing of coherent spins for multifunctional semiconductor spintronics

AU - Malajovich, I.

AU - Berry, J. J.

AU - Samarth, N.

AU - Awschalom, D. D.

PY - 2001/6/14

Y1 - 2001/6/14

N2 - Recent studies of n-type semiconductors have demonstrated spin-coherent transport over macroscopic distances, with spin-coherence times exceeding 100 ns; such materials are therefore potentially useful building blocks for spin-polarized electronics ('spintronics'). Spin injection into a semiconductor (a necessary step for spin electronics) has proved difficult; the only successful approach involves classical injection of spins from magnetic semiconductors. Other work has shown that optical excitation can provide a short (<500 ps) non-equilibrium burst of coherent spin transfer across a GaAs/ZnSe interface, but less than 10% of the total spin crosses into the ZnSe layer, leaving long-lived spins trapped in the GaAs layer (ref. 9). Here we report a 'persistent' spin-conduction mode in biased semiconductor heterostructures, in which the sourcing of coherent spin transfer lasts at least 1-2 orders of magnitude longer than in unbiased structures. We use time-resolved Kerr spectroscopy to distinguish several parallel channels of interlayer spin-coherent injection. The relative increase in spin-coherent injection is up to 500% in the biased structures, and up to 4,000% when p-n junctions are used to impose a built-in bias. These experiments reveal promising opportunities for multifunctional spin electronic devices (such as spin transistors that combine memory and logic functions), in which the amplitude and phase of the net spin current are controlled by either electrical or magnetic fields.

AB - Recent studies of n-type semiconductors have demonstrated spin-coherent transport over macroscopic distances, with spin-coherence times exceeding 100 ns; such materials are therefore potentially useful building blocks for spin-polarized electronics ('spintronics'). Spin injection into a semiconductor (a necessary step for spin electronics) has proved difficult; the only successful approach involves classical injection of spins from magnetic semiconductors. Other work has shown that optical excitation can provide a short (<500 ps) non-equilibrium burst of coherent spin transfer across a GaAs/ZnSe interface, but less than 10% of the total spin crosses into the ZnSe layer, leaving long-lived spins trapped in the GaAs layer (ref. 9). Here we report a 'persistent' spin-conduction mode in biased semiconductor heterostructures, in which the sourcing of coherent spin transfer lasts at least 1-2 orders of magnitude longer than in unbiased structures. We use time-resolved Kerr spectroscopy to distinguish several parallel channels of interlayer spin-coherent injection. The relative increase in spin-coherent injection is up to 500% in the biased structures, and up to 4,000% when p-n junctions are used to impose a built-in bias. These experiments reveal promising opportunities for multifunctional spin electronic devices (such as spin transistors that combine memory and logic functions), in which the amplitude and phase of the net spin current are controlled by either electrical or magnetic fields.

UR - http://www.scopus.com/inward/record.url?scp=0035859045&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035859045&partnerID=8YFLogxK

U2 - 10.1038/35081014

DO - 10.1038/35081014

M3 - Article

C2 - 11459049

AN - SCOPUS:0035859045

VL - 411

SP - 770

EP - 772

JO - Nature

JF - Nature

SN - 0028-0836

IS - 6839

ER -