@article{33389, keywords = {temperature, oxide, Perovskite, oxides, semiconductor, chemistry, semiconductors, semiconductor quantum dots, titanium, Calcium compounds, Perovskite solar cells, Stark effect, Circularly polarized optical pulse, Dielectric confinement, Inorganic semiconductors, Light-matter coupling, Light-matter interactions, Perovskite thin films, Solution processability, Straightforward strategy, Semiconductor quantum wells, calcium derivative, halogen, quantum theory, thermodynamics, Halogens}, author = {D Giovanni and W.K Chong and H.A Dewi and K Thirumal and I Neogi and Ramamoorthy Ramesh and S Mhaisalkar and N Mathews and T.C Sum}, title = {Tunable room-temperature spin-selective optical Stark effect in solution-processed layered halide perovskites}, abstract = {Ultrafast spin manipulation for opto-spin logic applications requires material systems that have strong spinselective light-matter interaction. Conventional inorganic semiconductor nanostructures [for example, epitaxial II to VI quantum dots and III to V multiple quantum wells (MQWs)] are considered forerunners but encounter challenges such as lattice matching and cryogenic cooling requirements. Two-dimensional halide perovskite semiconductors, combining intrinsic tunable MQW structures and large oscillator strengths with facile solution processability, can offer breakthroughs in this area. We demonstrate novel room-temperature, strong ultrafast spin-selective optical Stark effect in solution-processed (C6H4FC2H4NH3)2PbI4 perovskite thin films. Exciton spin states are selectively tuned by ∼6.3 meV using circularly polarized optical pulses without any external photonic cavity (that is, corresponding to a Rabi energy of ∼55 meV and equivalent to applying a 70 T magnetic field), which is much larger than any conventional system. The facile halide and organic replacement in these perovskites affords control of the dielectric confinement and thus presents a straightforward strategy for tuning light-matter coupling strength. © 2016 The Authors.}, year = {2016}, journal = {Science Advances}, volume = {2}, number = {6}, publisher = {American Association for the Advancement of Science}, issn = {23752548}, doi = {10.1126/sciadv.1600477}, note = {cited By 33}, language = {eng}, }