X- and Q-band EPR with cryogenic amplifiers independent of sample temperature.

Cryoprobe EPR LNA Noise SNR Sensitivity

Journal

Journal of magnetic resonance (San Diego, Calif. : 1997)
ISSN: 1096-0856
Titre abrégé: J Magn Reson
Pays: United States
ID NLM: 9707935

Informations de publication

Date de publication:
Jan 2023
Historique:
received: 27 10 2022
revised: 03 12 2022
accepted: 04 12 2022
pubmed: 15 12 2022
medline: 15 12 2022
entrez: 14 12 2022
Statut: ppublish

Résumé

Inspired by the success of NMR cryoprobes, we recently reported a leap in X-band EPR sensitivity by equipping an ordinary EPR probehead with a cryogenic low-noise microwave amplifier placed closed to the sample in the same cryostat [Šimėnas et al. J. Magn. Reson.322, 106876 (2021)]. Here, we explore, theoretically and experimentally, a more general approach, where the amplifier temperature is independent of the sample temperature. This approach brings a number of important advantages, enabling sensitivity improvement irrespective of sample temperature, as well as making it more practical to combine with ENDOR and Q-band resonators, where space in the sample cryostat is often limited. Our experimental realisation places the cryogenic preamplifier within an external closed-cycle cryostat, and we show CW and pulsed EPR and ENDOR sensitivity improvements at both X- and Q-bands with negligible dependence on sample temperature. The cryoprobe delivers signal-to-noise ratio enhancements that reduce the equivalent pulsed EPR measurement time by 16× at X-band and close to 5× at Q-band. Using the theoretical framework we discuss further improvements of this approach which could be used to achieve even greater sensitivity.

Identifiants

pubmed: 36516664
pii: S1090-7807(22)00214-2
doi: 10.1016/j.jmr.2022.107356
pii:
doi:

Types de publication

Journal Article

Langues

eng

Sous-ensembles de citation

IM

Pagination

107356

Informations de copyright

Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.

Déclaration de conflit d'intérêts

Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [Mantas Simenas reports a relationship with Amplify My Probe Ltd. that includes: equity or stocks. Vidmantas Kalendra reports a relationship with Amplify My Probe Ltd. that includes: equity or stocks.]

Auteurs

Vidmantas Kalendra (V)

Faculty of Physics, Vilnius University, Sauletekio 3, LT-10257 Vilnius, Lithuania; Amplify My Probe Ltd., London NW1 1NJ, UK.

Justinas Turčak (J)

Faculty of Physics, Vilnius University, Sauletekio 3, LT-10257 Vilnius, Lithuania.

Jūras Banys (J)

Faculty of Physics, Vilnius University, Sauletekio 3, LT-10257 Vilnius, Lithuania.

John J L Morton (JJL)

London Centre for Nanotechnology, University College London, London WC1H 0AH, UK; Dept. of Electronic & Electrical Engineering, University College London, London WC1E 7JE, UK.

Mantas Šimėnas (M)

Faculty of Physics, Vilnius University, Sauletekio 3, LT-10257 Vilnius, Lithuania. Electronic address: mantas.simenas@ff.vu.lt.

Classifications MeSH