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Controlling Positronium Annihilation with Electric Fields.

A M Alonso1, B S Cooper1, A Deller1

  • 1Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom.

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This summary is machine-generated.

Controlling positronium (Ps) annihilation dynamics is achieved using electric and magnetic fields. This method allows tuning Ps states for enhanced detection and optimized two-photon excitation processes.

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Area of Science:

  • Atomic Physics
  • Quantum Mechanics

Background:

  • Positronium (Ps) is a fundamental leptonic atom formed by an electron and a positron.
  • Understanding Ps annihilation dynamics is crucial for various applications, including materials science and fundamental physics tests.

Purpose of the Study:

  • To investigate the control of excited positronium annihilation dynamics using external fields.
  • To explore the manipulation of Ps states for improved detection and excitation efficiency.

Main Methods:

  • Optical excitation of Ps atoms to n=2 sublevels.
  • Application of parallel electric and magnetic fields to create mixed states.
  • Analysis of annihilation radiation and lifetimes of the mixed states.

Main Results:

  • Annihilation dynamics of excited Ps atoms can be precisely controlled by parallel electric and magnetic fields.
  • Mixed states with controllable short-lived and long-lived character were generated.
  • Optimized resonance-enhanced two-photon excitation processes were demonstrated by exploiting controlled lifetimes.

Conclusions:

  • External fields offer a powerful tool to tailor Ps properties for specific applications.
  • The presented method provides a practical approach for Ps detection and advanced excitation schemes.
  • Efficient production of long-lived pure 2^{3}S_{1} positronium atoms is achievable via single-photon excitation of mixed states.