Research output: Contribution to journal › Article › peer-review
Magnetic field dependence of triplet-state ONP : theoretical analysis in terms of level anti-crossings. / Sosnovsky, Denis V.; Ivanov, Konstantin L.
In: Molecular Physics, Vol. 117, No. 19, 01.01.2019, p. 2740-2755.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Magnetic field dependence of triplet-state ONP
T2 - theoretical analysis in terms of level anti-crossings
AU - Sosnovsky, Denis V.
AU - Ivanov, Konstantin L.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - A theoretical approach to Optical Nuclear Polarisation (ONP) is described, which is based on the analysis of Level Anti-Crossings (LACs) in triplet states. Here we consider ONP formed in molecular crystals doped with suitable guest molecules and ONP generated in diamond crystals containing negatively charged nitrogen-vacancy (NV–) centres. In both cases, electron spin polarisation of triplet states generated by light excitation is transferred to nuclei giving rise to ONP. Polarisation transfer is most efficient at LACs; for this reason, we consider in detail crossings of electron–nuclear energy levels and the role of different perturbation terms (coming from isotropic and anisotropic hyperfine coupling, zero-field splitting and sample orientation), which turn these crossings into LACs and give rise to ONP. Analytical results are supported by numerical calculations of the ONP field dependences. Thus, the outlined LAC analysis is a useful approach for interpreting the ONP magnetic field dependence.
AB - A theoretical approach to Optical Nuclear Polarisation (ONP) is described, which is based on the analysis of Level Anti-Crossings (LACs) in triplet states. Here we consider ONP formed in molecular crystals doped with suitable guest molecules and ONP generated in diamond crystals containing negatively charged nitrogen-vacancy (NV–) centres. In both cases, electron spin polarisation of triplet states generated by light excitation is transferred to nuclei giving rise to ONP. Polarisation transfer is most efficient at LACs; for this reason, we consider in detail crossings of electron–nuclear energy levels and the role of different perturbation terms (coming from isotropic and anisotropic hyperfine coupling, zero-field splitting and sample orientation), which turn these crossings into LACs and give rise to ONP. Analytical results are supported by numerical calculations of the ONP field dependences. Thus, the outlined LAC analysis is a useful approach for interpreting the ONP magnetic field dependence.
KW - molecular crystals
KW - NV-centres
KW - optical nuclear polarisation
KW - Spin hyperpolarisation
KW - triplet states
KW - MECHANISM
KW - OPTICAL NUCLEAR-POLARIZATION
KW - RELAXATION
KW - ANTHRACENE-TETRACYANOBENZENE
KW - SPIN POLARIZATION
KW - PROTONS
KW - ORIENTATION
KW - CONSEQUENCE
KW - CRYSTALS
KW - HYPERPOLARIZATION
UR - http://www.scopus.com/inward/record.url?scp=85051978467&partnerID=8YFLogxK
U2 - 10.1080/00268976.2018.1504996
DO - 10.1080/00268976.2018.1504996
M3 - Article
AN - SCOPUS:85051978467
VL - 117
SP - 2740
EP - 2755
JO - Molecular Physics
JF - Molecular Physics
SN - 0026-8976
IS - 19
ER -
ID: 16113470