• Nguyen, Tho
• Amerling, Eric
• Pham, Minh
• Whittaker-Brooks, Luisa

Abstract

e studied spin dynamics of charge carriers in the superlattice-like Ruddlesden-Popper hybrid lead iodide perovskite semiconductors, 2D (BA) 2 (MA)Pb 2 I 7 (with MA = CH 3 NH 3 , and BA = CH 3 (CH 2 ) 3 NH 3 ), and 3D MAPbI 3 using the magnetic field effect (MFE) on conductivity and electroluminescence in their light emitting diodes (LEDs) at cryogenic temperatures. The semiconductors with distinct structural/bulk inversion symmetry breaking, when combined with colossal intrinsic spin–orbit coupling (SOC), theoretically give rise to giant Rashba-type SOC. We found that the magneto-conductance (MC) magnitude increases monotonically with the emission intensity and saturates at ≈0.05% and 0.11% for the MAPbI 3 and (BA) 2 (MA)Pb 2 I 7 , respectively. The magneto-electroluminescence (MEL) response with similar line shapes as the MC response has a significantly larger magnitude, and essentially stays constant at ≈0.22% and ≈0.20% for MAPbI 3 and (BA) 2 (MA)Pb 2 I 7 , respectively. The sign and magnitude of the MC and MEL responses can be quantitatively explained in the framework of the Δg-based excitonic model using rate equations. Remarkably, the width of the MEL response in those materials linearly increases with increasing the applied electric field, where the Rashba coefficient in (BA) 2 (MA)Pb 2 I 7 is estimated to be about 7 times larger than that in MAPbI 3 . Our studies might have significant impact on future development of electrically-controlled spin logic devices via Rashba-like effects.

Topics

• perovskite
• impedance spectroscopy
• semiconductor