Project Details
Pulsed Electron Paramagnetic Resonance at Millikelvin Temperatures
Applicant
Professor Dr. Hans Hübl
Subject Area
Analytical Chemistry
Term
from 2015 to 2020
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 276452390
The technological improvement of electron paramagnetic resonance spectroscopy for material science and biological applications is at the heart of the Priority Program 1601. This objective is based on two main innovation branches: First, the improvement of the detection sensitivity by employing ultra-sensitive microwave analysis techniques as well as optimized low-loss and downsized microwave detection circuits. Second, an improved control over the spin ensembles by the development of optimized pulse sequences, because integrated sub-wavelength microwave circuits come with the cost of an increased microwave magnetic field inhomogeneity. Harnessing these new developments gives access to increased detection sensitivity, higher signal-to-noise ratio corresponding to shorter acquisition times, and the ability to investigate smaller sample volumes, which in turn will allow for highly spatially resolved studies.The current project aims at the improvement of the microwave signal techniques. To this end, we will facilitate the ultra-sensitive microwave spectroscopy techniques originally developed for quantum information applications, which are capable to detect signal amplitudes on the single photon level. We will transfer these approaches to ultra-sensitive microwave analysis tools for EPR spectroscopy. In this context, low-temperature setups will provide a key development platform, as they offer an experimental environment with a well-characterized and understood noise environment, designed to suppress thermal noise in the microwave frequency band. Furthermore, this detection sensitivity allows for performing single-shot EPR experiments, where the excitation pulse and the resulting response of the spin ensemble can be studied in-situ. Combined with the microwave magnetic field inhomogeneity of the employed superconducing microwave resonators, the low available excitation powers, and the long spin life and decoherence times, these systems provide a new playground for optimal control pulses.Thus, we expect that this extremely low-noise environment will be the ideal platform for the development of ultra-sensitive microwave detection techniques for EPR.
DFG Programme
Priority Programmes