A broad-band light-emitting diode was achieved in a single-layer device based on pure poly(9,9′-dioctylfluorene-co-bis-N,N′-(4-butylphenyl)-bis-N,N′-phenyl-1,4-phenylenediamine) (PFB). Electromer emission was observed in the red with a center wavelength of about 620 nm in electroluminescence (EL) spectrum. This kind of emission exhibits strong dependence on the thickness of the PFB layer, so that the shape of the EL spectrum may be adjusted through changing the thickness of the active polymer layer to balance between the intrinsic PFB emission in the blue and the electromer emission in the red. Thus, white light emission may be achieved from such a single-layer single-material diode.

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Atomically resolved and well-ordered field ion images of several silicon surfaces have been obtained. For a carefully cleaned Si tip, after annealing at 800 °C for several minutes, very well-ordered atomic structures develop on high index planes such as the (230), (135), (124), (234), (123), (113), (115), and (317). Many of them are reconstructed. Two structures coexist for the (230) plane. Also, many two-dimensional defects can be seen.