Effect of Electron-Nuclear Hyperfine Interactions on Multiple-Quantum Coherences in Photogenerated Covalent Radical (Qubit) Pairs

Jordan N. Nelson, Jinyuan Zhang, Jiawang Zhou, Brandon K. Rugg, Matthew D. Krzyaniak, Michael R Wasielewski

Research output: Contribution to journalArticle

Abstract

Ultrafast photodriven electron transfer reactions starting from an excited singlet state in an organic donor-acceptor molecule can generate a spin-correlated radical pair (RP) with an initially entangled spin state that may prove useful as a two-qubit pair in quantum information protocols. Here we investigate the effects of modulating electron-nuclear hyperfine coupling by rapidly transferring an electron between two equivalent sites comprising the reduced acceptor of the RP. A covalent electron donor-acceptor molecule including a tetrathiafulvalene (TTF) donor, a 4-aminonaphthalene-1,8-imide (ANI) chromophoric primary acceptor, and an m-xylene bridged cyclophane having two equivalent pyromellitimides (PI2), TTF-ANI-PI2, as a secondary acceptor was synthesized along with an analogous molecule having one pyromellitimide (PI) acceptor, TTF-ANI-PI. Photoexcitation of ANI within each molecule results in sub-nanosecond formation of TTF+•-ANI-PI-• and TTF+•-ANI-PI2 -•. The effect of reducing electron-nuclear hyperfine interactions in TTF+•-ANI-PI2 -• relative to TTF+•-ANI-PI-• on decoherence of multiple-quantum coherences has been measured by pulse-EPR spectroscopy. This contribution is especially relevant in the absence of modulation of exchange or dipolar interactions, as with the RP at a fixed distance in the molecules in this work. The theoretical prediction of the contribution from an ensemble of hyperfine interactions to decoherence in these RPs is shown to be less than the full width at half-maximum of the quantum beat frequencies measured experimentally. Pulse bandwidth and off-resonant excitation by square microwave pulses are proposed as larger contributors to decoherence in these molecules than the hyperfine interactions, and specific pulse shapes relevant to arbitrary waveform generation are introduced.

Original languageEnglish
Pages (from-to)9392-9402
Number of pages11
JournalJournal of Physical Chemistry A
Volume122
Issue number49
DOIs
Publication statusPublished - Dec 13 2018

Fingerprint

1-Naphthylamine
Imides
imides
Electrons
Molecules
electrons
interactions
molecules
pulses
beat frequencies
Photoexcitation
xylene
tetrathiafulvalene
Full width at half maximum
photoexcitation
Excited states
excitation
Paramagnetic resonance
Laser pulses
electron transfer

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Effect of Electron-Nuclear Hyperfine Interactions on Multiple-Quantum Coherences in Photogenerated Covalent Radical (Qubit) Pairs. / Nelson, Jordan N.; Zhang, Jinyuan; Zhou, Jiawang; Rugg, Brandon K.; Krzyaniak, Matthew D.; Wasielewski, Michael R.

In: Journal of Physical Chemistry A, Vol. 122, No. 49, 13.12.2018, p. 9392-9402.

Research output: Contribution to journalArticle

Nelson, Jordan N. ; Zhang, Jinyuan ; Zhou, Jiawang ; Rugg, Brandon K. ; Krzyaniak, Matthew D. ; Wasielewski, Michael R. / Effect of Electron-Nuclear Hyperfine Interactions on Multiple-Quantum Coherences in Photogenerated Covalent Radical (Qubit) Pairs. In: Journal of Physical Chemistry A. 2018 ; Vol. 122, No. 49. pp. 9392-9402.
@article{2e273210013a4e6abeaade532fd80a6e,
title = "Effect of Electron-Nuclear Hyperfine Interactions on Multiple-Quantum Coherences in Photogenerated Covalent Radical (Qubit) Pairs",
abstract = "Ultrafast photodriven electron transfer reactions starting from an excited singlet state in an organic donor-acceptor molecule can generate a spin-correlated radical pair (RP) with an initially entangled spin state that may prove useful as a two-qubit pair in quantum information protocols. Here we investigate the effects of modulating electron-nuclear hyperfine coupling by rapidly transferring an electron between two equivalent sites comprising the reduced acceptor of the RP. A covalent electron donor-acceptor molecule including a tetrathiafulvalene (TTF) donor, a 4-aminonaphthalene-1,8-imide (ANI) chromophoric primary acceptor, and an m-xylene bridged cyclophane having two equivalent pyromellitimides (PI2), TTF-ANI-PI2, as a secondary acceptor was synthesized along with an analogous molecule having one pyromellitimide (PI) acceptor, TTF-ANI-PI. Photoexcitation of ANI within each molecule results in sub-nanosecond formation of TTF+•-ANI-PI-• and TTF+•-ANI-PI2 -•. The effect of reducing electron-nuclear hyperfine interactions in TTF+•-ANI-PI2 -• relative to TTF+•-ANI-PI-• on decoherence of multiple-quantum coherences has been measured by pulse-EPR spectroscopy. This contribution is especially relevant in the absence of modulation of exchange or dipolar interactions, as with the RP at a fixed distance in the molecules in this work. The theoretical prediction of the contribution from an ensemble of hyperfine interactions to decoherence in these RPs is shown to be less than the full width at half-maximum of the quantum beat frequencies measured experimentally. Pulse bandwidth and off-resonant excitation by square microwave pulses are proposed as larger contributors to decoherence in these molecules than the hyperfine interactions, and specific pulse shapes relevant to arbitrary waveform generation are introduced.",
author = "Nelson, {Jordan N.} and Jinyuan Zhang and Jiawang Zhou and Rugg, {Brandon K.} and Krzyaniak, {Matthew D.} and Wasielewski, {Michael R}",
year = "2018",
month = "12",
day = "13",
doi = "10.1021/acs.jpca.8b07556",
language = "English",
volume = "122",
pages = "9392--9402",
journal = "Journal of Physical Chemistry A",
issn = "1089-5639",
publisher = "American Chemical Society",
number = "49",

}

TY - JOUR

T1 - Effect of Electron-Nuclear Hyperfine Interactions on Multiple-Quantum Coherences in Photogenerated Covalent Radical (Qubit) Pairs

AU - Nelson, Jordan N.

AU - Zhang, Jinyuan

AU - Zhou, Jiawang

AU - Rugg, Brandon K.

AU - Krzyaniak, Matthew D.

AU - Wasielewski, Michael R

PY - 2018/12/13

Y1 - 2018/12/13

N2 - Ultrafast photodriven electron transfer reactions starting from an excited singlet state in an organic donor-acceptor molecule can generate a spin-correlated radical pair (RP) with an initially entangled spin state that may prove useful as a two-qubit pair in quantum information protocols. Here we investigate the effects of modulating electron-nuclear hyperfine coupling by rapidly transferring an electron between two equivalent sites comprising the reduced acceptor of the RP. A covalent electron donor-acceptor molecule including a tetrathiafulvalene (TTF) donor, a 4-aminonaphthalene-1,8-imide (ANI) chromophoric primary acceptor, and an m-xylene bridged cyclophane having two equivalent pyromellitimides (PI2), TTF-ANI-PI2, as a secondary acceptor was synthesized along with an analogous molecule having one pyromellitimide (PI) acceptor, TTF-ANI-PI. Photoexcitation of ANI within each molecule results in sub-nanosecond formation of TTF+•-ANI-PI-• and TTF+•-ANI-PI2 -•. The effect of reducing electron-nuclear hyperfine interactions in TTF+•-ANI-PI2 -• relative to TTF+•-ANI-PI-• on decoherence of multiple-quantum coherences has been measured by pulse-EPR spectroscopy. This contribution is especially relevant in the absence of modulation of exchange or dipolar interactions, as with the RP at a fixed distance in the molecules in this work. The theoretical prediction of the contribution from an ensemble of hyperfine interactions to decoherence in these RPs is shown to be less than the full width at half-maximum of the quantum beat frequencies measured experimentally. Pulse bandwidth and off-resonant excitation by square microwave pulses are proposed as larger contributors to decoherence in these molecules than the hyperfine interactions, and specific pulse shapes relevant to arbitrary waveform generation are introduced.

AB - Ultrafast photodriven electron transfer reactions starting from an excited singlet state in an organic donor-acceptor molecule can generate a spin-correlated radical pair (RP) with an initially entangled spin state that may prove useful as a two-qubit pair in quantum information protocols. Here we investigate the effects of modulating electron-nuclear hyperfine coupling by rapidly transferring an electron between two equivalent sites comprising the reduced acceptor of the RP. A covalent electron donor-acceptor molecule including a tetrathiafulvalene (TTF) donor, a 4-aminonaphthalene-1,8-imide (ANI) chromophoric primary acceptor, and an m-xylene bridged cyclophane having two equivalent pyromellitimides (PI2), TTF-ANI-PI2, as a secondary acceptor was synthesized along with an analogous molecule having one pyromellitimide (PI) acceptor, TTF-ANI-PI. Photoexcitation of ANI within each molecule results in sub-nanosecond formation of TTF+•-ANI-PI-• and TTF+•-ANI-PI2 -•. The effect of reducing electron-nuclear hyperfine interactions in TTF+•-ANI-PI2 -• relative to TTF+•-ANI-PI-• on decoherence of multiple-quantum coherences has been measured by pulse-EPR spectroscopy. This contribution is especially relevant in the absence of modulation of exchange or dipolar interactions, as with the RP at a fixed distance in the molecules in this work. The theoretical prediction of the contribution from an ensemble of hyperfine interactions to decoherence in these RPs is shown to be less than the full width at half-maximum of the quantum beat frequencies measured experimentally. Pulse bandwidth and off-resonant excitation by square microwave pulses are proposed as larger contributors to decoherence in these molecules than the hyperfine interactions, and specific pulse shapes relevant to arbitrary waveform generation are introduced.

UR - http://www.scopus.com/inward/record.url?scp=85058533830&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85058533830&partnerID=8YFLogxK

U2 - 10.1021/acs.jpca.8b07556

DO - 10.1021/acs.jpca.8b07556

M3 - Article

VL - 122

SP - 9392

EP - 9402

JO - Journal of Physical Chemistry A

JF - Journal of Physical Chemistry A

SN - 1089-5639

IS - 49

ER -