Chirality‐Induced Spin Selectivity: An Enabling Technology for Quantum Applications

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(28)

Published: May 12, 2023

Molecular spins are promising building blocks of future quantum technologies thanks to the unparalleled flexibility provided by chemistry, which allows design complex structures targeted for specific applications. However, their weak interaction with external stimuli makes it difficult access state at single-molecule level, a fundamental tool use, example, in computing and sensing. Here, an innovative solution exploiting interplay between chirality magnetism using chirality-induced spin selectivity effect on electron transfer processes is foreseen. It envisioned use spin-to-charge conversion mechanism that can be realized connecting molecular qubit dyad where donor acceptor linked chiral bridge. By numerical simulations based realistic parameters, shown could enable initialization, manipulation, single-spin readout qubits qudits even relatively high temperatures.

Language: Английский

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Entangled spin-polarized excitons from singlet fission in a rigid dimer

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: March 2, 2023

Singlet fission, a process that splits singlet exciton into biexciton, has promise in quantum information. We report time-resolved electron paramagnetic resonance measurements on conformationally well-defined acene dimer molecule, TIPS-BP1', designed to exhibit strongly state-selective relaxation specific magnetic spin sublevels. The resulting optically pumped polarization is nearly pure initial state from the ensemble. long-lived coherences modulate signal intrinsically, allowing measurement scheme substantially removes noise and uncertainty spectra. A nonadiabatic transition theory with minimal number of spectroscopic parameters allows quantitative assignment interpretation In this work, we show rigid TIPS-BP1' supports persistent at temperatures far higher than those used conventional superconducting hardware.

Language: Английский

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Singlet fission as a polarized spin generator for dynamic nuclear polarization

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: March 1, 2023

Singlet fission (SF), converting a singlet excited state into spin-correlated triplet-pair state, is an effective way to generate spin quintet in organic materials. Although its application photovoltaics as exciton multiplier has been extensively studied, the use of unique degree freedom largely unexplored. Here, we demonstrate that polarization multiexcitons generated by SF improves sensitivity magnetic resonance water molecules through dynamic nuclear (DNP). We form supramolecular assemblies few pentacene chromophores and SF-born spins achieve DNP water-glycerol, most basic biological matrix, evidenced dependence enhancement on field microwave power. Our demonstration opens polarized generator bio-quantum technology.

Language: Английский

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A molecular perspective on quantum information

Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences, Journal Year: 2023, Volume and Issue: 479(2279)

Published: Nov. 1, 2023

Some of the fundamentals quantum information science are described, including concepts resources, states and mixedness states. The explanations detailed include a combination basic facts with fully worked examples, some more advanced topics. principles illustrated chemical examples drawn from singlet fission, photophysics radicals, molecular excitons, electron transfer so on. Suggestions for prospects challenges field discussed.

Language: Английский

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Spin-related excited-state phenomena in photochemistry

National Science Review, Journal Year: 2024, Volume and Issue: 11(9)

Published: July 18, 2024

ABSTRACT The spin of electrons plays a vital role in chemical reactions and processes, the excited state generated by absorption photons shows abundant spin-related phenomena. However, importance electron photochemistry studies has been rarely mentioned or summarized. In this review, we briefly introduce concept based on multiplicity state, which leads to observation various photophysical properties photochemical reactivities. Then, focus recent advances terms light-induced magnetic properties, excited-state magneto-optical effects spin-dependent reactions. review aims provide comprehensive overview utilize manipulating above processes. Finally, discuss existing challenges emerging field future opportunities such as smart materials, optical information technology spin-enhanced photocatalysis.

Language: Английский

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Oriented Triplet Excitons as Long-Lived Electron Spin Qutrits in a Molecular Donor–Acceptor Single Cocrystal

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 146(1), P. 1089 - 1099

Published: Dec. 29, 2023

The photogeneration of multiple unpaired electron spins within molecules is a promising route to applications in quantum information science because they can be initialized into well-defined, multilevel states (S > 1/2) and reproducibly fabricated by chemical synthesis. However, coherent manipulation these spin difficult realize typical molecular systems due the lack selective addressability short coherence times transitions. Here, challenges are addressed using donor–acceptor single cocrystals composed pyrene naphthalene dianhydride host spatially oriented triplet excitons, which exhibit photogenerated qutrit properties. Time-resolved paramagnetic resonance (TREPR) spectroscopy demonstrates that orienting excitons crystal platform imparts narrow, well-resolved, tunable resonances EPR spectrum, allowing sublevel Pulse-EPR reveals at temperatures above 30 K, decoherence driven exciton diffusion. limited electronic dipolar coupling below where T2 varies nonlinearly with optical excitation density annihilation. Overall, an optimized time = 7.1 μs 20 K achieved. These results provide important insights designing solid-state excitonic materials improved

Language: Английский

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Molecular Control of Triplet-Pair Spin Polarization and Its Optoelectronic Magnetic Resonance Probes

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 57(1), P. 59 - 69

Published: Dec. 16, 2023

ConspectusPreparing and manipulating pure magnetic states in molecular systems are the key initial requirements for harnessing power of synthetic chemistry to drive practical quantum sensing computing technologies. One route achieving requisite higher spin organic exploits phenomenon singlet fission, which produces pairs triplet excited from initially photoexcited singlets assemblies with multiple chromophores. The resulting characterized by total (quintet, triplet, or singlet) its projection onto a specified field axis. These typically highly polarized but exhibit an impure population pattern. Herein, we report prediction experimental verification design rules that single state describe progress toward realization.A vital feature this work is close partnership among theory, chemical synthesis, spectroscopy. We begin presenting our theoretical framework understanding manifold interconversion fission systems. This theory makes specific testable predictions about intermolecular structure orientation relative external should lead preparation provides powerful tool interpreting spectra. then test these through detailed spectroscopy experiments on series new architectures meet one more identified structural criteria. Many rely synthesis molecules features unique effort: rigid bridges between chromophores dimers, heteroacenes tailored singlet/triplet-pair energy level matching, side-group engineering produce crystal structures. evolution revealed application development several resonance methods, each has different sensitivities relevance environments relevant applications.Our prove be remarkably consistent results, though experimentally meeting all prescriptions demanded true pure-state remains challenge. Our spectra agree model triplet-pair behavior, including funneling ms = 0 sublevel quintet under conditions dimers crystals, showing subject control design. Moreover, demonstration novel and/or sensitive detection mechanisms systems, photoluminescence (PL), photoinduced absorption (PA), magnetoconductance (MC), points way both deeper how evolve technologically feasible routes at single-molecule limit desirable computational applications.

Language: Английский

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Multiexciton quintet state populations in a rigid pyrene-bridged parallel tetracene dimer

Chemical Science, Journal Year: 2023, Volume and Issue: 14(41), P. 11554 - 11565

Published: Jan. 1, 2023

The multiexciton quintet state, 5TT, generated as a singlet fission intermediate in pairs of molecular chromophores, is promising candidate qubit or qudit future quantum information science schemes. In this work, we synthesize pyrene-bridged parallel tetracene dimer, TPT, with an optimized interchromophore coupling strength to prevent the dissociation 5TT two decorrelated triplet (T1) states, which would contaminate spin-state mixture. Long-lived and strongly spin-polarized pure state population observed via transient absorption spectroscopy transient/pulsed electron paramagnetic resonance spectroscopy, its lifetime estimated be >35 µs, dephasing time (T2) for 5TT-based measured 726 ns at 10 K. Direct relaxation from 1TT ground does diminish overall excited population, but exclusive large enough persistent density pulsed echo determination spin coherence consistent recent theoretical models that predict such behavior strict chromophore alignment exchange coupling.

Language: Английский

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Macrocyclic Parallel Dimer Showing Quantum Coherence of Quintet Multiexcitons at Room Temperature

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(37), P. 25527 - 25535

Published: Sept. 9, 2024

Singlet fission (SF) is a promising approach in quantum information science because it can generate spin-entangled quintet triplet pairs by photoexcitation independent of temperature. However, still challenging to rationally achieve coherence at room temperature, which requires precise control the orientation and dynamics pairs. Here we show that multiexcitons be achieved temperature arranging two pentacene chromophores parallel close proximity within macrocycle. By making dynamic covalent Schiff-base bonds between aldehyde-modified derivatives, macrocyclic dimer-1 (

Language: Английский

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Giant magneto-photoluminescence at ultralow field in organic microcrystal arrays for on-chip optical magnetometer

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: May 11, 2024

Abstract Optical detection of magnetic field is appealing for integrated photonics; however, the light-matter interaction usually weak at low field. Here we observe that photoluminescence (PL) decreases by > 40% 10 mT in rubrene microcrystals (RMCs) prepared a capillary-bridge assembly method. The giant magneto-PL (MPL) relies on singlet-triplet conversion involving triplet-triplet pairs, through processes singlet fission (SF) and triplet fusion (TF) during radiative decay. Importantly, size RMCs critical maximizing MPL as it influences photophysical spin state conversion. SF/TF process quantified measuring prompt/delayed PL with time-resolved spectroscopies, which shows geminate associated pairs are responsible MPL. Furthermore, RMC-based magnetometer constructed an optical chip, takes advantages remarkable low-field sensitivity over broad range frequencies, representing prototype emerging opto-spintronic molecular devices.

Language: Английский

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