Regensburg 2019 – wissenschaftliches Programm
DY 37.6: Vortrag
Mittwoch, 3. April 2019, 16:45–17:00, H6
Motional narrowing in microwave graphs — •Tobias Hofmann1, Aimaiti Rehemanjiang1, Ulrich Kuhl1,2, and Hans-Jürgen Stöckmann1 — 1Fachbereich Physik, Philipps-Universität Marburg, Renthof 5, D-35032 Marburg, Germany — 2InPhyNi, Université Côte d’Azur, 06100 Nice, France
Motional narrowing is a well-known phenomenon in nuclear magnetic resonance (NMR) spectroscopy and is caused by rapidly moving atoms in an inhomogeneous magnetic environment . If there are just two sites involved, realized e. g. by a molecular flip between two geometries or configurational changes in a glassy network, an analytical solution is known . Also in superconducting qubits with two stochastically fluctuating energies an analogue of the effect could be seen .
To simulate the effects of motional averaging and motional narrowing in microwave graphs stochastic switching has to be employed. This means to flip a resonance frequency of the graph between two values stochastically. The flip frequency is thereby comparable to or greater than the energy difference of the two resonance frequencies involved. By using a special diode circuit this frequency regime of typically some 10 MHz becomes accessible and the effects of motional averaging and motional narrowing can be observed in microwave graphs. The setup and experimental results will be presented.
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