The strong spin-orbit interaction in the organic-inorganic perovskites tied to the incorporation of heavy elements (e.g. Pb, I) makes these materials interesting for applications in spintronics. Due to a lack of inversion symmetry associated with distortions of the metal-halide octahedra, the Rashba effect (used e.g. in spin field-effect transistors and spin filters) has been predicted to be much larger in these materials than in traditional III-V semiconductors such as GaAs, supported by the recent observation of a near record Rashba spin splitting in CH 3 NH 3 PbBr 3 using angle-resolved photoemission spectroscopy (ARPES). More experimental studies are needed to confirm and quantify the presence of Rashba effects in the organic-inorganic perovskite family of materials. Here we apply time-resolved circular dichroism techniques to the study of carrier spin dynamics in a 2D perovskite thin film [(BA) 2 MAPb 2 I 7 ; BA = CH 3 (CH 2 ) 3 NH 3 , MA = CH 3 NH 3 ]. Our findings confirm the presence of a Rashba spin splitting via the dominance of precessional spin relaxation induced by the Rashba effective magnetic field. The size of the Rashba spin splitting in our system was extracted from simulations of the measured spin dynamics incorporating LO-phonon and electron-electron scattering, yielding a value of 10 meV at an electron energy of 50 meV above the band gap, representing a 20 times larger value than in GaAs quantum wells.The hybrid organic-inorganic perovskites have gained considerable attention in recent years due to their outstanding performance as absorbing layers in photovoltaics [1]. This success has led to a comprehensive research effort with the aim to unravel their photophysical properties [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], and to move beyond CH 3 NH 3 PbI 3 and explore other material compositions including 2D perovskites [19][20][21][22][23][24]. This burgeoning family of materials offers properties that can be tailored to a broad range of applications in opto-electronics, including photovoltaics [1,23,25], field-effect transistors [26,27], hard radiation detectors [28], light-emitting diodes [29][30][31], lasers [32], and optical sensors [33].The hybrid perovskites are characterized by strong spin-orbit coupling (SOC) tied to the constituent heavy elements [34]. These strong spin-orbit effects make the perovskite family of materials attractive for applications in semiconductor spintronics and spin optoelectronics [35][36][37][38][39][40][41][42][43][44][45]. SOC leads to a giant (∼1 eV) splitting of the lowest two conduction bands and influences the band gap and carrier effective masses [46,47]. In conjunction with a lack of inversion symmetry, SOC also leads to an effective magnetic field that lifts the degeneracy of the carrier spin states within each band [35]. While this effect has many origins in semiconductors tied to different sources of inversion asymmetry [48][49][50][51][52], it is most commonly referred to as the Rashba effect after Bychkov and Rashba analyzed the ...

We present a driving scheme for solid-state quantum emitters, referred to as Notch-filtered Adiabatic Rapid Passage (NARP), that utilizes frequency-swept pulses containing a spectral hole resonant with the optical transition in the emitter. NARP enables high-fidelity state inversion and exhibits robustness to variations in the laser pulse parameters, benefits that derive from the insensitivity of the condition for adiabatic evolution. NARP also offers the advantage of immunity to phonon-mediated excitation-induced dephasing when positively-chirped control pulses are used. Our resonant driving approach could be combined with spectral filtering of the scattered pump light and photonic devices for enhanced collection efficiency to realize simultaneous high indistinguishability and brightness in single photon source applications.

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Trapped ions are one of the leading platforms for quantum information processing, exhibiting the highest gate and measurement fidelities of all contending hardware. In order to realize a universal quantum computer with trapped ions, independent and parallel control over the state of each qubit is necessary. The manipulation of individual qubit states in an ion chain via stimulated Raman transitions generally requires light focused on individual ions. In this manuscript, we present a novel, guided-light individual addressing system for hyperfine Ba+ qubits. The system takes advantage of laser-written waveguide technology, enabled by the atomic structure of Ba+, allowing the use of visible light to drive Raman transitions. Such waveguides define the spatial mode of light, suppressing aberrations that would have otherwise accumulated in a free-space optics set up. As a result, we demonstrate a nearest neighbor relative intensity crosstalk on the order of 10−4, without any active aberration compensation. This is comparable to or better than other previous demonstrations of individual addressing. At the same time, our modular approach provides independent and agile control over the amplitude, frequency, and phase of each channel; combining the strengths of previous implementations.

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