2000/07/06 by C. Gilles, Gilles, C., P. Bonville +5
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Advanced Electron Microscopy Techniques and Applications #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Phytoplasmas and Hemiptera pathogens #RNA and protein synthesis mechanisms #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.cond-mat/0007090
4 pages, 3 figures
arxiv created 2000/07/06 · openalex publication_date 2000/07/06 · arxiv updated 2009/11/30 · openalex created_date 2022/12/12 · openalex updated_date 2026/07/28
The magnetic behaviour of nanoparticles of antiferromagnetic ferritin, with a mean Fe loading of 410 atoms per core, has been investigated by 57Fe Mossbauer absorption spectroscopy down to very low temperature (34mK). In previous experi- ments of frequency dependent magnetic susceptibility and magnetic noise performed at 25mK in similar samples, it was claimed that a resonance at a frequency of about 10**8 Hz, due to a macroscopic coherent state, had been observed. However, our search of incoherent tunnel fluctuations around 10**8 Hz using 57Fe Mossbauer spectroscopy, whose "window" of measurement of fluctuation frequencies lies in this frequency range, was unsuccessful. This casts a doubt about the previous observa- tion of macroscopic quantum coherence in ferritin.