Highly polarized single-crystal organic light-emitting devices with low turn-on voltage and high brightness

We develop linearly-polarized single-crystal OLEDs, which exhibit a degree of polarization of 0.95 for electroluminescence, a turn-on voltage of 2.5 V, an exceptionally high brightness of 200 000 cd m −2 , and a current density surpassing 300 A cm −2 .