Polarized electroluminescence

Figure 5-24. u) Polar represenlalion (Irom —90 io +90 ) lor lire angular dependence ol lliioreseenee anisotropy (ll-V) in Th films willi grain sizes of 1500 mil (open squares). 000 nm (filled circles), and 200 nm (open circles), b) The angular dependence of electroluminescence anisotropy (H-V) measured from the LED contacted pari of the same samples. 

Optically active polymers are potentially very useful in areas such as asymmetric catalysis, nonlinear optics, polarized photo and electroluminescence, and enantioselective separation and sensing.26 Transition metal coupling polymerization has also been applied to the synthesis of these polymers.27 For example, from the Ni(II)-catalyzed polymerization, a regioregular head-to-tail polymer 32 was obtained (Scheme 9.17).28 This polymer is optically active because of the optically active chiral side chains. 

Having investigated the electrochemical behavior of ZnSe, and in view of the well-known blue luminescence of the compound, the previous authors extended their work to study electroluminescence from I-doped n-ZnSe crystals under anodic polarization in aqueous media containing metal ions such as Cu(II) and Sn(II) [123]. 

Gautron J, Dalbera IP, Lemasson P (1980) Electroluminescence of the electrolyte/n-ZnSe junction under anodic polarization. Surf Sci 99 300-308... 

Polarized luminescence from oriented molecular materials 1999 Ladder-type materials 1999 Electroluminescence in organics... 

M. Grell, D.D.C. Bradley, M. Inbasekaran, and E.P. Woo, A glass-forming conjugated main-chain liquid crystal polymer for polarized electroluminescence applications, Adv. Mater., 9 798-802, 1997. 

M. Grell, W. Knoll, D. Lupo, A. Miesel, T. Miteva, D. Neher, H.-G. Nothofer, U. Scherf, and A. Yasuda, Blue polarized electroluminescence from a liquid crystalline polyfluorene, Adv. Mater., 11 671-675, 1999. 

A. Bolognesi, G. Bajo, J. Paloheimo, T. Ostergard, and H. Stubb, Polarized electroluminescence from an oriented poly(3-alkylthiophene) Langmuir-Blodgett structure, Adv. Mater., 9 121-124,1997. 

P. Dyreklev, M. Beggren, O. Inganas, M.R. Andersson, O. Wennerstrom, and T. Hjertberg, Polarized electroluminescence from an oriented substituted polythiophene in a light emitting diode, Adv. Mater., 1 43-45, 1995. 

Linearly Polarized Photo- and Electroluminescence from Uniaxially... 

LINEARLY POLARIZED PHOTO- AND ELECTROLUMINESCENCE FROM UNIAXIALLY ORIENTED MOLECULES... 

FIGURE 5.4 Chemical structures of photo- and electroluminescent polymers employed for polarized LEDs poly(2-methoxy-5-(2 -ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV) poly[2,5-dioctyloxy-l, 4-diethynyl-phenylene-a/t-2,5,-bis(2 -ethylhexyloxy)-l,4-phenylene] (EHO-OPPE) poly(p-phenylene), PPP poly(3-(4-octylphenyl)-2,2 -bithiophene), PTOPT poly(p-phenylene vinylene), PPV poly(3-alkylthio-phene vinylene), P3AT Acetoxy-PPY PPV-polyester, poly(9,9-dialkyl fluorene), PF. 

FIGURE 5.8 Electroluminescence from an LED based on ITO-rubbed PPV-aligned poly(9,9-dioctyl fluorene)/Ca recorded through a polarizer oriented parallel (triangles) and perpendicular (circles) to the orientation direction. (From Whitehead, K.S., Grell, M., Bradley, D.D.C., Jandke, M., and Strohriegl, P., Appl. Phys. Lett., 76, 2946, 2000. With permission.)... 

D Neher, Polyfluorene homopolymers conjugated liquid-crystalline polymers for bright blue emission and polarized electroluminescence, Macromol. Rapid Common., 22 1365-1385, 2001. 

M Flamaguchi and K Yoshino, Polarized electroluminescence from rubbing-aligned poly(2,5-dinonyloxy-l,4-phenylenevinylene) films, Appl. Phys. Lett., 67 3381-3383, 1995. 

M Jandke, P Strohriegl, J Gmeiner, W Brutting, and M Schwoerer, Polarized electroluminescence from rubbing-aligned poly(phenylenevinylene), Adv. Mater., 11 1518-1521, 1999. 

Y Yoshida, JP Ni, N Tanigaki, and K Yase, Polarized electroluminescence of oligophenyl thin films prepared on friction transferred poly(p-phenylenes), Mol. Cryst. Liq. Cryst., 370 69-72, 2001. 

E Arias, T Maillou, I Moggio, D Guillon, J Le Moigne, and B Geffroy, Amphiphilic phenylene-ethynylene polymers and oligomers for polarized electroluminescence, Synth. Met., 127 229-231, 2002. 

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