TY - JOUR
T1 - The influence of triplet exciton and charge transfer energy alignment on organic magnetoresistance
AU - Janssen, P.
AU - Wouters, S.H.W.
AU - Cox, M.
AU - Koopmans, B.
PY - 2014
Y1 - 2014
N2 - Recently, it was discovered that the current through an organic semiconductor, sandwiched
between two non-magnetic electrodes, can be changed significantly (up to 25%)
by applying a small (a few millitesla) magnetic field. At present, the microscopic mechanisms
underlying this so-called organic magnetoresistance (OMAR) are intensively being
debated. One of the mechanisms which can successfully describe the magnetic field effects
on the current in pristine organic semiconductor devices uses the reactions of triplet excitons
and polarons. Here, we present a proof of concept study in which we tune these interactions
in the device by deliberately doping our devices with fullerene, creating additional
charge transfer states (CTS). By engineering devices with different energetic alignments of
the CTS and triplet exciton, we can influence the triplet exciton density in the device. We
correlate pronounced changes in the magnetic field effect magnitude and lineshape to the
energy of the CTS with respect to the triplet exciton.
2014 Elsevier B.V. All rights reserved.
AB - Recently, it was discovered that the current through an organic semiconductor, sandwiched
between two non-magnetic electrodes, can be changed significantly (up to 25%)
by applying a small (a few millitesla) magnetic field. At present, the microscopic mechanisms
underlying this so-called organic magnetoresistance (OMAR) are intensively being
debated. One of the mechanisms which can successfully describe the magnetic field effects
on the current in pristine organic semiconductor devices uses the reactions of triplet excitons
and polarons. Here, we present a proof of concept study in which we tune these interactions
in the device by deliberately doping our devices with fullerene, creating additional
charge transfer states (CTS). By engineering devices with different energetic alignments of
the CTS and triplet exciton, we can influence the triplet exciton density in the device. We
correlate pronounced changes in the magnetic field effect magnitude and lineshape to the
energy of the CTS with respect to the triplet exciton.
2014 Elsevier B.V. All rights reserved.
U2 - 10.1016/j.orgel.2014.01.010
DO - 10.1016/j.orgel.2014.01.010
M3 - Article
VL - 15
SP - 743
EP - 750
JO - Organic Electronics
JF - Organic Electronics
SN - 1566-1199
ER -