Session A6 - Molecular Nanomagnets.
INVITED session, Monday morning, March 22
516AB, Palais des Congres
In my talk I will comment on the experimental detection of coherent microwave radiation emitted from molecular clusters. I will start discussing the high resolution detection of resonant frequencies of microwave resonators via magnetic measurements. The equilibrium magnetization and the ac susceptibility of molecular magnets in this experiments show sharp peaks for the resonant frequencies of the device. This effect has been used to study the influence of the microwave absorption on the spin tunneling rate in several molecular clusters. Then I will discuss the spin quantum dynamics of crystals of molecular clusters inside a resonant cavity and placed between Fabry-Perot superconductor mirrors. The main idea behind this is that the magnetic relaxation of molecular clusters is very much affected when they are inside microwave resonators. I will thereafter address the main topic of my talk. For that I will discuss experimental results using an indium antimonide (InSb) bolometer inside a stainless steel waveguide in which the crystals of molecular clusters are also placed. All this was set inside a SQUID magnetometer that allowed us to change the magnetic field and measure the magnetization at the same time that the InSb detected the radiation emitted from the molecular clusters.
References: 1.- R. Amigó et al., Appl. Phys. Lett. 82, 4528 (2003). 2.- R. Amigó et al., Europhys. Lett. 64, 158 (2003). 3.- R. Amigó et al., Phys. Rev. B 67, 220402(R) (2003). 4.- J. Tejada et al., Phys. Rev. B 68, 014431 (2003).