Header

UZH-Logo

Maintenance Infos

Upgrade of a low-temperature scanning tunneling microscope for electron-spin resonance


Natterer, Fabian D; Patthey, François; Bilgeri, Tobias; Forrester, Patrick R; Weiss, Nicolas; Brune, Harald (2019). Upgrade of a low-temperature scanning tunneling microscope for electron-spin resonance. Review of Scientific Instruments, 90:013706.

Abstract

Electron spin resonance with a scanning tunneling microscope (ESR-STM) combines the high energy resolution of spin resonance spectroscopy with the atomic scale control and spatial resolution of STM. Here we describe the upgrade of a helium-3 STM with a 2D vector-field magnet (Bz = 8.0 T, Bx = 0.8 T) to an ESR-STM. The system is capable of delivering radio frequency (RF) power to the tunnel junction at frequencies up to 30 GHz. We demonstrate magnetic field-sweep ESR for the model system TiH/MgO/Ag(100) and find a magnetic moment of (1.004 ± 0.001) μB. Our upgrade enables to toggle between a DC mode, where the STM is operated with the regular control electronics, and an ultrafast-pulsed mode that uses an arbitrary waveform generator for pump-probe spectroscopy or reading of spin-states. Both modes allow for simultaneous radiofrequency excitation, which we add via a resistive pick-off tee to the bias voltage path. The RF cabling from room temperature to the 350 mK stage has an average attenuation of 18 dB between 5 and 25 GHz. The cable segment between the 350 mK stage and the STM tip presently attenuates an additional 34+5−3 dB from 10 to 26 GHz and 38+3−2 dB between 20 and 30 GHz. We discuss our transmission losses and indicate ways to reduce this attenuation. We finally demonstrate how to synchronize the arrival times of RF and DC pulses coming from different paths to the STM junction, a prerequisite for future pulsed ESR experiments.

Abstract

Electron spin resonance with a scanning tunneling microscope (ESR-STM) combines the high energy resolution of spin resonance spectroscopy with the atomic scale control and spatial resolution of STM. Here we describe the upgrade of a helium-3 STM with a 2D vector-field magnet (Bz = 8.0 T, Bx = 0.8 T) to an ESR-STM. The system is capable of delivering radio frequency (RF) power to the tunnel junction at frequencies up to 30 GHz. We demonstrate magnetic field-sweep ESR for the model system TiH/MgO/Ag(100) and find a magnetic moment of (1.004 ± 0.001) μB. Our upgrade enables to toggle between a DC mode, where the STM is operated with the regular control electronics, and an ultrafast-pulsed mode that uses an arbitrary waveform generator for pump-probe spectroscopy or reading of spin-states. Both modes allow for simultaneous radiofrequency excitation, which we add via a resistive pick-off tee to the bias voltage path. The RF cabling from room temperature to the 350 mK stage has an average attenuation of 18 dB between 5 and 25 GHz. The cable segment between the 350 mK stage and the STM tip presently attenuates an additional 34+5−3 dB from 10 to 26 GHz and 38+3−2 dB between 20 and 30 GHz. We discuss our transmission losses and indicate ways to reduce this attenuation. We finally demonstrate how to synchronize the arrival times of RF and DC pulses coming from different paths to the STM junction, a prerequisite for future pulsed ESR experiments.

Statistics

Citations

Dimensions.ai Metrics
14 citations in Web of Science®
12 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

69 downloads since deposited on 15 Mar 2019
45 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Physics Institute
Dewey Decimal Classification:530 Physics
Scopus Subject Areas:Physical Sciences > Instrumentation
Uncontrolled Keywords:Instrumentation
Language:English
Date:1 January 2019
Deposited On:15 Mar 2019 12:50
Last Modified:29 Jul 2020 10:17
Publisher:American Institute of Physics
ISSN:0034-6748
OA Status:Green
Publisher DOI:https://doi.org/10.1063/1.5065384
PubMed ID:30709206
Project Information:
  • : FunderSNSF
  • : Grant ID200020_176932
  • : Project TitleQuantum Magnets at Surfaces
  • : FunderSNSF
  • : Grant IDPZ00P2_167965
  • : Project TitleSingle atom and molecule radio wave absorption spectroscopy

Download

Green Open Access

Download PDF  'Upgrade of a low-temperature scanning tunneling microscope for electron-spin resonance'.
Preview
Content: Accepted Version
Filetype: PDF
Size: 1MB
View at publisher
Download PDF  'Upgrade of a low-temperature scanning tunneling microscope for electron-spin resonance'.
Preview
Content: Published Version
Filetype: PDF
Size: 2MB