関連する実験動画
Updated: Feb 6, 2026

10:53
Scanning-probe Single-electron Capacitance Spectroscopy
Published on: July 30, 2013
13.5K
低寄生容量の多層極低温粉末フィルター
Itishree Pradhan1, Hao Li1, Alina Rupp1,2
1Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8581, Japan.
The Review of scientific instruments
|February 4, 2026
まとめ
高周波無線周波数(RF)信号を遮断し、不要な電気的干渉を低減する新しい極低温粉末フィルターを開発しました。この革新的な設計は、サンプル加熱を防ぎ、高感度セットアップでの測定性能を維持します。
科学分野:
- 物理学
- 電気工学
- 材料科学
背景:
- 従来の粉末フィルターは、無線周波数(RF)信号減衰のために表皮効果を利用しています。
- これらのフィルターはしばしば高い寄生容量を示し、高感度測定における帯域幅を制限します。
- 寄生容量は、極低温セットアップで不要なサンプル加熱を引き起こす可能性があります。
研究 の 目的:
- 高RF減衰と低寄生容量を持つ極低温粉末フィルターを開発すること。
- RF信号の侵入とそれに伴うサンプル加熱を軽減すること。
- 高感度測定システムの性能を維持すること。
主な方法:
- 多層粉末フィルターを設計・製造しました。
- 寄生容量を最小限に抑えるために、新しいハウジング構造を利用しました。
- ギガヘルツ範囲でRF減衰をテストしました。
主要な成果:
- ギガヘルツ範囲で高いRF信号減衰を達成しました。
- 従来の設計と比較して、接地面への寄生容量を大幅に削減しました。
- 性能低下なしにサンプル加熱の抑制を実証しました。
結論:
- 多層粉末フィルターは、従来の設計の限界を効果的に解決します。
- この技術により、RFが豊富な極低温環境での高感度測定が可能になります。
- 科学機器におけるRF誘起加熱を防ぐソリューションを提供します。
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