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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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Indoor channel modeling for continuous variable quantum key distribution in the terahertz band
Optics Express
|October 29, 2020
Summary
A new indoor channel model demonstrates the feasibility of continuous-variable quantum key distribution (CVQKD) in the terahertz (THz) band. Multi-path propagation limits indoor CVQKD to two meters, but high-gain antennas can extend this range.
Area of Science:
- Quantum Information Science
- Optical Communications
- Terahertz Technology
Background:
- Continuous-variable quantum key distribution (CVQKD) offers secure wireless access for short-distance, high-rate communications.
- Existing CVQKD research lacks indoor-specific channel models, hindering practical implementation.
Purpose of the Study:
- To establish a novel indoor channel model for terahertz (THz) band CVQKD.
- To evaluate the performance of CVQKD systems under indoor multi-path propagation conditions.
- To assess the impact of various channel parameters on CVQKD feasibility.
Main Methods:
- Development of an indoor channel model incorporating frequency, water-vapor density, antenna gain, and reflection loss.
- Implementation of both active and passive state preparation schemes.
- Utilization of ray-tracing numerical simulations to analyze multi-path propagation effects.
Main Results:
- The established indoor channel model confirms the feasibility of THz CVQKD.
- Multi-path propagation significantly degrades indoor CVQKD performance.
- A maximum transmission distance of two meters at 410 GHz was achieved for both preparation schemes.
- High-gain antennas extended the transmission distance to 35 meters (passive) and 20 meters (active).
Conclusions:
- Indoor CVQKD in the THz band is feasible but requires careful channel modeling.
- Mitigation strategies, such as high-gain antennas, are crucial for overcoming multi-path limitations.
- This research provides a foundation for practical indoor quantum communication systems.
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