Superradiant properties of 4,4′-bis(1H-phenanthro[9,10-d]imidazol-2-yl)biphenyl and how a laser dye with exceptional stability can be obtained in only one synthetic step

The extremely facile synthesis of a very stable laser dye with superradiant properties is reported. The laser action of the dye is demonstrated through a transverse pumping scheme with the advantage that no elaborate laser resonator is required due to the very high gain of the laser medium. The emitted light exhibits speckle, spatial coherence and the ability to be collimated by a lens. (C) 2001 Elsevier Science Ltd. All rights reserved.