Revealing the properties of the radical-pair magnetoreceptor using pulsed photo-excitation timed with pulsed rf

TL;DR

This paper proposes a novel experimental method using pulsed laser and radio-frequency pulses to definitively detect and analyze the properties of the radical-pair magnetoreceptor responsible for magnetic navigation in birds.

Contribution

It introduces a new experimental approach combining pulsed photo-excitation and rf pulses to identify and characterize the radical-pair magnetoreceptor in avian species.

Findings

Prediction of a resonance effect in magnetic orientation versus rf-pulse delay

Resonance position reveals the singlet-triplet mixing time

Unambiguous detection of the radical-pair mechanism in birds

Abstract

The radical-pair mechanism is understood to underlie the magnetic navigation capability of birds and possibly other species. Experiments with birds have provided indirect and in cases conflicting evidence on the actual existence of this mechanism. We here propose a new experiment that can unambiguously identify the presence of the radical-pair magnetoreceptor in birds and unravel some of its basic properties. The proposed experiment is based on modulated light excitation with a pulsed laser, combined with delayed radio-frequency magnetic field pulses. We predict a resonance effect in the birds' magnetic orientation versus the rf-pulse delay time. The resonance's position reflects the singlet-triplet mixing time of the magnetoreceptor.