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Displacement of Propagating Squeezed Microwave States
Kirill G Fedorov1, L Zhong1,2,3, S Pogorzalek1,2
1Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, D-85748 Garching, Germany.
Physical Review Letters
|July 23, 2016
Summary
Researchers successfully displaced propagating quantum states of light, specifically squeezed microwave states. This quantum operation maintained squeezing levels and constant path entanglement, crucial for quantum communication and teleportation.
Area of Science:
- Quantum optics
- Quantum information science
- Microwave quantum state engineering
Background:
- Displacement operations are fundamental for quantum communication and quantum teleportation.
- Previous implementations have been limited in their ability to maintain quantum state properties.
Purpose of the Study:
- To implement and characterize the displacement operation for propagating squeezed microwave states.
- To investigate the impact of displacement on squeezing levels and path entanglement.
Main Methods:
- Experimental implementation of displacement for squeezed microwave states.
- Characterization of quantum state properties using homodyne detection.
- Analysis of squeezing levels and path entanglement as a function of displacement power.
Main Results:
- Successful displacement of propagating squeezed microwave states.
- No degradation of squeezing levels observed even for strong displacement amplitudes.
- Path entanglement remained constant across a wide range of displacement power.
Conclusions:
- The displacement operation is robust for propagating squeezed microwave states.
- This technique is suitable for quantum communication protocols requiring high fidelity quantum state manipulation.
- The findings pave the way for advanced quantum networking and computation using microwave photons.
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