Non-exponential tunneling and control of microwave absorption lineshapes via Fano resonance for electrons on Helium

Solomon Duki; Harsh Mathur

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arXiv · 0804.2210

Non-exponential tunneling and control of microwave absorption lineshapes via Fano resonance for electrons on Helium

Solomon Duki·Harsh Mathur

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Abstract

We consider the application of a small in-plane magnetic field to electrons on a helium surface in a perpendicular magnetic field. Certain states that were bound to the helium surface then dissolve into the continuum turning into long-lived resonances. As a result microwave absorption lines acquire an asymmetric Fano lineshape that is tunable by varying the microwave polarisation or the in-plane magnetic field. Electrons trapped in a formerly bound state will tunnel off the surface of helium; we show that under suitable circumstances this ``radioactive decay'' can show damped oscillations rather than a simple exponential decay. The mechanism for oscillatory exponential decay is not specific to electrons on Helium and this effect may also be relevant elsewhere in physics.

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Solomon Duki, Harsh Mathur. 2008-04-14. Non-exponential tunneling and control of microwave absorption lineshapes via Fano resonance for electrons on Helium. https://arxiv.org/abs/0804.2210

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