Pressure dependence of singlet and triplet excitons in amorphous polymer semiconductors K. Paudel, D. Moghe, M. Chandrasekhar, P. Yu, S. Ramasesha, U. Scherf and S. Guha EPL, 104 2 (2013) 27008 Published online: 20 November 2013 DOI: 10.1209/0295-5075/104/27008