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Comparison of cryogenic low-pass filters
M Thalmann1, H-F Pernau1, C Strunk2
1Department of Physics, University of Konstanz, 78464 Konstanz, Germany.
The Review of Scientific Instruments
|December 3, 2017
Summary
Effective low-pass filtering and thermalization are crucial for low-temperature quantum measurements. This study introduces a novel filter design to improve noise reduction and thermalization for experiments below 10 millikelvin.
Area of Science:
- Experimental Physics
- Quantum Measurement
- Cryogenics
Background:
- High-energy resolution at low temperatures necessitates effective noise filtering and electronic system thermalization.
- Existing filter designs struggle to meet the demands of millikelvin temperatures and eliminate spurious high-frequency noise.
- The growing interest in quantum phenomena necessitates advanced cryogenic measurement techniques.
Purpose of the Study:
- To analyze commonly used filter types for cryogenic measurements.
- To introduce a novel compact ferrite-based filter optimized for frequencies above 20 GHz.
- To develop an improved, adaptable filtering scheme for millikelvin quantum applications.
Main Methods:
- Comprehensive analysis of existing cryogenic filter designs.
- Development and characterization of a novel ferrite compound filter.
- Design of an improved filtering scheme with adaptable broad-band low-pass characteristics.
Main Results:
- Identified limitations of current filter concepts below 10 mK.
- Introduced a compact ferrite filter effective above 20 GHz.
- Developed an improved filtering scheme for millikelvin applications.
Conclusions:
- A single filter concept is often insufficient for effective thermalization and noise elimination.
- The novel ferrite filter and improved scheme enhance cryogenic measurement capabilities.
- The developed filtering scheme is suitable for low-level quantum measurements down to few millikelvin.
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