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 spin-selective 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.
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore 637371, Singapore.; Energy Research Institute @NTU (ERI@N), Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, S2-B3a-01, Singapore 639798, Singapore.
authors.forename: David
authors.identifier: 0000-0002-2764-5613
authors.initials: D
authors.lastname: Giovanni
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore 637371, Singapore.; Energy Research Institute @NTU (ERI@N), Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, S2-B3a-01, Singapore 639798, Singapore.
authors.forename: Wee Kiang
authors.identifier: 0000-0001-6059-3918
authors.initials: WK
authors.lastname: Chong
authors.affiliation: ERI@N, Research Techno Plaza, X-Frontier Block, Level 5, 50 Nanyang Drive, Singapore 637553, Singapore.
authors.forename: Herlina Arianita
authors.initials: HA
authors.lastname: Dewi
authors.affiliation: ERI@N, Research Techno Plaza, X-Frontier Block, Level 5, 50 Nanyang Drive, Singapore 637553, Singapore.
authors.forename: Krishnamoorthy
authors.identifier: 0000-0002-9217-8089
authors.initials: K
authors.lastname: Thirumal
authors.affiliation: ERI@N, Research Techno Plaza, X-Frontier Block, Level 5, 50 Nanyang Drive, Singapore 637553, Singapore.
authors.forename: Ishita
authors.identifier: 0000-0002-7707-0512
authors.initials: I
authors.lastname: Neogi
authors.affiliation: Department of Materials Science and Engineering and Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA.
authors.forename: Ramamoorthy
authors.initials: R
authors.lastname: Ramesh
authors.affiliation: ERI@N, Research Techno Plaza, X-Frontier Block, Level 5, 50 Nanyang Drive, Singapore 637553, Singapore.; School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, Singapore.
authors.forename: Subodh
authors.identifier: 0000-0002-9895-2426
authors.initials: S
authors.lastname: Mhaisalkar
authors.affiliation: ERI@N, Research Techno Plaza, X-Frontier Block, Level 5, 50 Nanyang Drive, Singapore 637553, Singapore.; School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, Singapore.
authors.forename: Nripan
authors.identifier: 0000-0001-5234-0822
authors.initials: N
authors.lastname: Mathews
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University (NTU), 21 Nanyang Link, Singapore 637371, Singapore.
authors.forename: Tze Chien
authors.identifier: 0000-0003-4049-2719
authors.initials: TC
authors.lastname: Sum
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry*; D006219:Halogens / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D011789:Quantum Theory; D012666:Semiconductors; D013696:Temperature; D013816:Thermodynamics; D014025:Titanium / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D006219:Halogens; D010087:Oxides; C059910:perovskite; D014025:Titanium
keywords: Layered Halide Perovskites; Non-linear; Optical Stark Effect; Rabi-splitting; Solution Processed; Spin-selective; Ultrafast; light-matter interactions; opto-spin-logic; room temperature