Development Of Organic Laser Device Under Electrical Pumping

In 1996, the research group of Heeger at University of California, Santa Barbara, reliazed the optically pumped solid-state conjugated polymer laser for the first time. From that time, electrically pumped organic laser is one of aims in the organic optoelectronics fields. This dissertation systemically summarizes design theory of electrically pumped organic microcavity semiconductor laser. Using the transfer matrix methods combined with microcavity theory, we simulated the optical properties of organic microccavity and DBR mirrors, and the standing wave field distribution of organic semiconductor lasers. Based on the principles of wavelength alignment between resonance peak and the fluorescence peak of organic laser material, and alignment between the antinode of cavity standing wave field and the active region, we can determine the distribution of organic layers in microcavity. Combined with the emission spectrum of organic laser material, we can simulate the center wavelength, FWHM, emission intensity of organic lasers. A model for electrical pumped organic microcavity laser has been proposed, by which we can simply estimate the threshold current density.Electrically pumped organic semiconductor lasers were realiazed with different emission color. We obtained UV organic light emitting devices that having high external quantum efficiency. High color purity UV OLEDs with EL emission peak between 367nm and 400nm, and FWHM of about 10nm have been obtained by restraining the visible light component in the emission due to the design of an unsymmetry microcavity structure. The maximum output power density of UV OLED was above 2mW/cm~2. The total thickness of organic layers in UV OLED is only about 50nm which breaks the general consensus in OLED community. White light devices with color render index of more than 90 were obtained by using UV OLEDs to excite trichromatic phosphors. On the basis of UV OLED, UV electrically pumped organic lasers were developed with peak wavelength at 398nm, and threshold current density of 700mA/cm~2.Electrically pumped organic lasers with green light emission based on C545T laser material were realized with the threshold current density of 200mA/cm~2, peak wavelength of 517nm, FWHM of 2.05nm, the beam quality factor (M2) of 22, waist radius w0 of 0.0768mm, waist position L0 of 90.67mm, the Rayleigh size Z0 of 1.83mm, and the far field divergence angle (theta) of 0.042 rad. Electrically pumped organic microcavity lasers based on Alq:DFQA material were fabricated with a peak wavelength of 552nm, and threshold current density of 286mA/cm~2. The spectral half width is narrowed from 5.44nm to 2.31nm. The output power is over 1 mW.Lasers at the wavelength of 650nm presently have important applications in the laser treatment and plastic optical fiber communication. Electrically pumped organic semiconductor lasers have been prepared with a hybrid heterostructure that having high-performance red laser dye DCJTI as the guest dopant, and NPB and Alq as the conjunct host materials. The lasers have a bottom emission structure, and show the lasing wavelength of 647nm, and threshold current density of 430mA/cm~2. The full width at half maximum is narrowed from 14.5nm to 4.02nm.