Scientists made a breakthrough in organic light emitting diode (OLED) technology that could lead to high-tech displays and even organic lasers.
OLEDs are made from carbon-containing materials, and could be used to make low-power displays that can be wrapped around other structures, the American Institute of Physics reported. OLEDs do not require back lighting light conventional LEDs, but can produce bright, low-power light sources when made with specific patterned structures.
The researchers said the key finding is to charge transport and recombination to nanoscale areas, which extends electroluminescent efficiency roll off the density at which the efficiency of the OLEDS is increased by as much as two orders of magnitude. This phenomenon is achieved through suppressing heating a preventing charge recombination. An important effect of suppressing roll-off is the increase of efficiency at high levels of brightness; this allows the OLEDs to achieve the same brightness while requiring less power.
"For years scientists working in organic semiconductors have dreamed of making electrically-driven organic lasers," said Thuc-Quyen Nguyen of the University of California, Santa Barbara, another co-author. "Lasers operate in extreme conditions with electric currents that are significantly higher than those used in common displays and lighting. At these high currents, energy loss processes become stronger and make lasing difficult.
"We see this work, which reduces some loss processes, as one step on the road toward realizing organic lasers."
The findings were published in a recent edition of the journal Applied Physics Letters.
