TY - JOUR
T1 - Controlling optical gain in semiconducting polymers with nanoscale chain positioning and alignment
AU - Martini, Ignacio B.
AU - Craig, Ian M.
AU - Molenkamp, William C.
AU - Miyata, Hirokatsu
AU - Tolbert, Sarah H.
AU - Schwartz, Benjamin J.
N1 - Funding Information:
This work was supported by Canon (S.H.T. and H.M.), by the Office of Naval Research under grant N00014-04-1-0410 (S.H.T. and B.J.S.), and by the National Science Foundation under grants DMR-0305254 (BJS) and CHE-0527015 (B.J.S. and S.H.T.). Correspondence and requests for materials should be addressed to S.T. or B.J.S. Supplementary information accompanies this paper on www.nature.com/naturenanotechnology.
PY - 2007/10
Y1 - 2007/10
N2 - We control the chain conformation of a semiconducting polymer by encapsulating it within the aligned nanopores of a silica host. The confinement leads to polarized, low-threshold amplified spontaneous emission from the polymer chains. The polymer enters the porous silica film from only one face and the filling of the pores is therefore graded. As a result, the profile of the index of refraction in the film is also graded, in the direction normal to the pores, so that the composite film forms a low-loss, graded-index waveguide. The aligned polymer chains plus naturally formed waveguide are ideally configured for optical gain, with a threshold for amplified spontaneous emission that is twenty times lower than in comparable unoriented polymer films. Moreover, the optimal conditions for ASE are met in only one spatial orientation and with one polarization. The results show that nanometre-scale control of semiconducting polymer chain orientation and position leads to novel and desirable optical properties.
AB - We control the chain conformation of a semiconducting polymer by encapsulating it within the aligned nanopores of a silica host. The confinement leads to polarized, low-threshold amplified spontaneous emission from the polymer chains. The polymer enters the porous silica film from only one face and the filling of the pores is therefore graded. As a result, the profile of the index of refraction in the film is also graded, in the direction normal to the pores, so that the composite film forms a low-loss, graded-index waveguide. The aligned polymer chains plus naturally formed waveguide are ideally configured for optical gain, with a threshold for amplified spontaneous emission that is twenty times lower than in comparable unoriented polymer films. Moreover, the optimal conditions for ASE are met in only one spatial orientation and with one polarization. The results show that nanometre-scale control of semiconducting polymer chain orientation and position leads to novel and desirable optical properties.
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U2 - 10.1038/nnano.2007.294
DO - 10.1038/nnano.2007.294
M3 - Article
C2 - 18654391
AN - SCOPUS:34948859032
SN - 1748-3387
VL - 2
SP - 647
EP - 652
JO - Nature Nanotechnology
JF - Nature Nanotechnology
IS - 10
ER -