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Pulsed electrically detected magnetic resonance spectroscopy (pEDMR) is
an only recently demonstrated method that allows the detection of
coherent electron spin motion by measuring electric current after a
coherent (pulsed) spin resonant excitation.
The observable of pEDMR (the current is controlled by spin-selection
rules) experiments is different from conventional pulsed electron spin
resonance (pESR) experiments (an x- and/or y-polarization component).
Therefore, the signals of spins observed with pEDMR may differ
from those with pESR. We have been investigating these differences
theoretically in a collaboration with Sergei
Baranovskii from Philipps Universitaet in Marburg and Klaus
Lips from Helmholtz-Zentrum Berlin fuer Materialien und Energie
(formerly Hahn- Meitner-Institut). One of the
remarkable insights gained in these studies is that spin-beat
oscillations in spin pairs can be much more pronounced in pEDMR signals
in comparison to pESR.
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Simulated
data of an electrically detected Rabi nutation as a function of the
applied microwave frequency in presence of a constant magnetic field.
The data show pronounced signals at two frequencies that correspond to
the electron spin resonances of the charge carriers within the charge
carrier pairs.
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a) Three-dimensional color plots of the
Fourier transform of a simulated pEDMR transient nutation experiment
as a function of the difference of the microwave frequency to the
average of the spin pairs Larmor frequencies. One can see the presence
of different nutation frequencies for different Larmor separations
within the charge carrier pairs indicative of the dominant beat
oscillation.
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Our recent results on this topic:
J.
Behrends*, K. Lips and
C. Boehme
Observation of precursor pair formation of
recombining charge carriers
Phys.
Rev. B 80, 045207 (2009). http://dx.doi.org/10.1103/PhysRevB.80.045207
(Editors' suggestion)
C. Michel, A.
Gliesche, S.D. Baranovskii*, K. Lips, F. Gebhard and C. Boehme*
, The influence of disorder on
electrically and optically detected electron spin nutation,
Phys.
Rev. B, 79, Brief Reports, 05221 (2009).
http://dx.doi.org/10.1103/PhysRevB.79.052201
A.
Gliesche, C. Michel, V.
Rajevac, K. Lips, S.D. Baranovskii, F. Gebhard and C. Boehme*
, Effect of exchange coupling
on
coherently controlled
spin-dependent transition rates,
Phys. Rev. B, 77, 245206 (2008).
http://dx.doi.org/10.1103/PhysRevB.77.245206
also
on arXiv:cond-mat/0801.1304 (2008). http://lanl.arxiv.org/abs/0801.1304
V. Rajevac, C. Boehme*, C.
Michel, A.
Gliesche, K.
Lips, S.
D. Baranovski, P.
Thomas,
Transport and recombination
through weakly
coupled localized spin pairs in semiconductors during coherent spin
excitation
, Phys.
Rev. B
74, 245206
(2006). http://dx.doi.org/10.1103/PhysRevB.74.245206
also on arXiv –
cond-mat: 0607627 (2006). http://lanl.arxiv.org/abs/cond-mat/0607627
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