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Published on: January 28, 2019
Zero to π Continuously Controllable Cross Phase Modulation in Doppler Broadened N-Type Electromagnetically Induced
1National Institute of Standard and Technology, Gaithersburg, Maryland USA 20899; State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China; Center for Cold Atom Physics, Chinese Academy of Sciences, Wuhan 430071, China.
Researchers demonstrated a controllable phase shift using electromagnetically induced transparency in Rubidium vapor. This breakthrough enables a continuously adjustable phase gate, crucial for quantum information processing applications.
Area of Science:
- Quantum Optics
- Atomic Physics
- Quantum Information Science
Background:
- Electromagnetically induced transparency (EIT) enables control over light-matter interactions.
- Controlling phase shifts is essential for developing quantum gates.
- Previous methods often required cryogenic temperatures or complex setups.
Purpose of the Study:
- To demonstrate a continuously controllable cross-phase-modulation (XPM) from zero to π.
- To implement a phase gate using this controllable XPM.
- To explore applications in quantum information processing.
Main Methods:
- Utilized an N-type EIT scheme in room-temperature 87Rb vapor.
- Employed a phase-control field to modulate the signal field's phase.
- Used an optical Mach-Zehnder interferometer to verify the phase gate functionality.
Main Results:
- Observed a continuously controllable phase shift from zero to π.
- Demonstrated that the signal field acquires a π phase shift relative to the reference light.
- Experimental results showed excellent agreement with theoretical calculations.
Conclusions:
- A room-temperature, continuously controllable phase gate based on EIT was successfully demonstrated.
- The developed method shows potential for creating orthogonal polarization/vector gates.
- This work advances the development of scalable quantum information processing technologies.
