Magnetoluminescence of light-emitting field-effect transistors based on alpha sexithiophene

We demonstrated the effect of a magnetic field on the luminous intensity and electric current of light-emitting field-effect transistors (LEFETs) based on alpha sexithiophene (alpha-6T). Sublimate-grade alpha-6T was thermally deposited on an n(+)-Si/300nm-SiO2 substrate with patterned asymmetric gold-aluminum electrodes to fabricate a bottom-contact LEFET. We observed an increase in luminous intensity of approximately 1.3% under a magnetic field of 100mT. A possible explanation for this is that the magnetic field increased the probability of singlet formation at the alpha-6T/Al interface. While the magneto-electroluminescence (MEL) was reported to be derived from the magneto-conductance (MC) in ordinary light emitting diodes, the MEL in LEFET was independent with MC. This indicates that the luminous efficiency can be improved by optimizing the magnetic field effect. (C) 2014 AIP Publishing LLC.