Detection sensitivity improvement on nuclear quadrupole resonance by high frequency modulation

2015 Fiscal Year Final Research Report

• Project/Area Number: 25289124
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Measurement engineering
• Research Institution: Osaka University
• Principal Investigator: Itozaki Hideo 大阪大学, 基礎工学研究科, 教授 (70354298)
• Co-Investigator(Kenkyū-buntansha): MIYATO Yuji 大阪大学, 大学院基礎工学研究科, 助教 (80512780)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 核四極共鳴 / 計測システム / 高感度化

Outline of Final Research Achievements

Nuclear quadrupole resonance (NQR) is known as one of the promising phenomena to realize the detection of hidden explosives. The short detectable distance due to the weak signal detection sensitivity was a significant issue for its practical use. This study was aimed to extend the detectable distance by improving the sensitivity. Firstly, we tried to increase the transmission efficiency by developing a new transmission and reception system, in which the transmission magnetic field with high frequency was modulated by resonance frequency of the target. However, our experiments showed that the excitation efficiency, caused by the nonlinearity of the spins, was very low. Then, we modified and optimized the antenna structure and the excitation pulse sequence in our conventional system. Finally, we achieved the improvement of NQR detection sensitivity. We also made portable landmine detector, and successfully demonstrated the effective detection of landmines buried in Republic of Colombia.

Free Research Field

計測工学