caa a22 4500 445365862 CHVBK 20180317142930.0 cr unu---uuuuu 170323e20110301xx s 000 0 eng 10.1007/s10909-010-0255-7 doi (NATIONALLICENCE)springer-10.1007/s10909-010-0255-7 An Operation Circuit of a Micro-SQUID Magnetometer below 1K [Elektronische Daten] [A. Yamaguchi, M. Wada, R. Tani, K. Takeda, T. Matsumoto, H. Kashiwaya, G. Motoyama, S. Kashiwaya, S. Ohkoshi, A. Sumiyama] We have been developing a micro superconducting quantum interference device (μ-SQUID) magnetometer for the study of quantum effects in μm- or nm-sized magnetic materials. In the μ-SQUID magnetometer, the sample is placed on the SQUID loop directly and the flux is detected by the loop itself. The close proximity between the sample and the SQUID loop is of great advantage for highly sensitive detection of magnetization from the tiny magnetic materials. However, the heat release during the operation of the SQUID could cause a great problem in experiments below 1K because of the close proximity of the SQUID and sample. Here we report a digital circuit for the μ-SQUID magnetometer which can reduce the heat release in the low temperature operation and whose parts are commercially available. The circuit consists of a FPGA-digital board with analog-to-digital and digital-to-analog converters, and an independent pre-amplifier. By using this circuit we succeeded in measuring quantum tunneling of magnetization in the single molecule magnet, Mn12Ph at 0.7K. Springer Science+Business Media, LLC, 2010 Macroscopic quantum tunneling in magnetization nationallicence Low temperature technique nationallicence Micro SQUID magnetometer nationallicence Yamaguchi A. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut Wada M. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut Tani R. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut Takeda K. Department of Chemistry, University of Tokyo, 113-0033, Tokyo, Japan aut Matsumoto T. Nanoelectronics Research Institute of Advanced Industrial Science and Technology (AIST), 305-8568, Tsukuba, Japan aut Kashiwaya H. Nanoelectronics Research Institute of Advanced Industrial Science and Technology (AIST), 305-8568, Tsukuba, Japan aut Motoyama G. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut Kashiwaya S. Nanoelectronics Research Institute of Advanced Industrial Science and Technology (AIST), 305-8568, Tsukuba, Japan aut Ohkoshi S. Department of Chemistry, University of Tokyo, 113-0033, Tokyo, Japan aut Sumiyama A. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut Journal of Low Temperature Physics Springer US; http://www.springer-ny.com 162/5-6(2011-03-01), 748-753 0022-2291 162:5-6<748 2011 162 10909 https://doi.org/10.1007/s10909-010-0255-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10909-010-0255-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Yamaguchi A. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut NATIONALLICENCE 700 1- Wada M. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut NATIONALLICENCE 700 1- Tani R. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut NATIONALLICENCE 700 1- Takeda K. Department of Chemistry, University of Tokyo, 113-0033, Tokyo, Japan aut NATIONALLICENCE 700 1- Matsumoto T. Nanoelectronics Research Institute of Advanced Industrial Science and Technology (AIST), 305-8568, Tsukuba, Japan aut NATIONALLICENCE 700 1- Kashiwaya H. Nanoelectronics Research Institute of Advanced Industrial Science and Technology (AIST), 305-8568, Tsukuba, Japan aut NATIONALLICENCE 700 1- Motoyama G. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut NATIONALLICENCE 700 1- Kashiwaya S. Nanoelectronics Research Institute of Advanced Industrial Science and Technology (AIST), 305-8568, Tsukuba, Japan aut NATIONALLICENCE 700 1- Ohkoshi S. Department of Chemistry, University of Tokyo, 113-0033, Tokyo, Japan aut NATIONALLICENCE 700 1- Sumiyama A. Graduate School of Material Science, University of Hyogo, 648-1297, Hyogo, Japan aut NATIONALLICENCE 773 0- Journal of Low Temperature Physics Springer US; http://www.springer-ny.com 162/5-6(2011-03-01), 748-753 0022-2291 162:5-6<748 2011 162 10909 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer