Extended Data Fig. 4: Simulated and measured PFs for the devices studied.

a, ODoS distribution simulated using dyadic Green’s functions^31,32 for structure C with a 15-nm-thick SF3Trz ETL and structure F with a 15-nm-thick BPyTP2 ETL. The triplet dipole position is in the middle of the EML with an isotropic orientation relative to the film plane. Dashed white lines separate regions of different optical modes. Structure F has a low-Q Ag/DBR cavity mode at k_x/k₀ < 1. The relative ODoS intensity is labelled by the colour bar on the right. The ODoS for structure C is multiplied by five for comparison. b, Simulated PF versus triplet emitter position for structures C and F for different cathode/ETL combinations. The horizontal and vertical dipoles are labelled by dash blue and red lines, respectively. The PF for isotropic dipoles is averaged over 67% horizontal (in-plane) and 33% vertical (orange line) dipoles. The measured PF of horizontal dipoles is labelled by diamonds at 45 nm from the cathode, corresponding to the centre of the 50-nm-thick EML. The simulated centre wavelength is 465 nm. c, Simulated PF of isotropic dipoles in half cavities H versus wavelength overlapped with the Ir(dmp)₃ PL spectrum. The exciton is located at 36 nm from the interfaces of Ag/BPyTP2, Al/BPyTP2, Ag/SF3Trz and Al/SF3Trz. d, Measured normalized decay rate, k_r/k_r,0 overlaid with the simulated PFs for horizontal (PF_hor) and isotropic (PF_iso) dipoles using the Green’s function method^31,32. Here k_r,0 is the decay rate of the bare EML.