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State transitions and decoherence in the avian compass
Vishvendra Singh Poonia1, Dipankar Saha1, Swaroop Ganguly1
1Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India.
Summary
The radical pair model explains avian navigation using quantum mechanics. Nuclear decoherence can surprisingly aid the geomagnetic compass, while environmental noise disrupts it.
Area of Science:
- Quantum Biology
- Biophysics
- Neuroethology
Background:
- The radical pair model is key to understanding avian magnetoreception.
- Quantum spin dynamics are crucial for the geomagnetic compass mechanism.
Purpose of the Study:
- To interpret radical pair model spin dynamics and decoherence microscopically.
- To clarify the roles of hyperfine and Zeeman interactions in avian navigation.
- To distinguish the effects of nuclear and environmental decoherence.
Main Methods:
- Microscopic state transition analysis of spin dynamics.
- Quantum information theory to quantify coherence.
- Modeling environmental decoherence with two noise models.
Main Results:
- Three regimes identified based on hyperfine interaction strength relative to geomagnetic Zeeman interaction.
- Avian compass likely functions in the large hyperfine interaction regime.
- Nuclear decoherence creates new spin dynamics structures at intermediate hyperfine strength.
Conclusions:
- Environmental decoherence disrupts avian compass function.
- Understanding spin dynamics and decoherence is vital for avian navigation research.
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