Aitor Lopeandia

Universitat Autònoma de Barcelona (UAB) and Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Associate Professor of Applied Physics at the Physics Department of the Universitat Autònoma de Barcelona, lecturing at Physics and Nanoscience and nanotechnology degrees from 2010. He received a PhD in Material Sciences (2007) at the Universitat Autònoma de Barcelona (Spain), working in the development of nanocalorimetric devices. As a postdoc he moved initially as José Castillejo fellow and after as IEF Marie Fellow (2008-2010) to the Institute Néel-CNRS (France), where he worked developing new calorimetric techniques to measure nanoscopic magnetic samples at low temperature ranges. In 2010, he was recipient of a ERG fellow returning to UAB as a lecturer professor and joining the group of nanomaterials and microsystems (GNaM) at UAB. From January 2021 he joined ICN2 as part of GTNAM group. His research interest is around the measurement of thermal properties of nanoscaled materials and their applications to energy.

Talk 5 (ONLINE)


Nanocalorimetry, thermodynamic properties, calorimetry, measuring techniques


Nanocalorimetry: Measuring heat capacity and phase transition in nanoscale samples


During last 20 years GTNAM-UAB group has devoted a significant effort towards the development of more sensitive calorimeters capable to efficiently measure small samples. Calorimetry is a suitable technique to characterize kinetic and thermodynamic properties of materials by measuring the heat released or absorbed by a material during any process. When the aim is to measure ultra-thin films or nanoscopic samples, the calorimetric measurements are troublesome [5], since the amount of energy released by a given reaction uses to be too small to be measured and analyzed with accuracy using conventional calorimeters (typically limited to samples of few miligrams). The fundamental problem on measuring small samples is related to the ratio between the heat capacity of the calorimetric cell and the heat capacity of the sample, since the calorimetric signal is proportional to the total addenda of the total calorimetric cell, but the transformation signal is only proportional to the sample.

The development of micromachining techniques associated to the Silicon technology has paved the scaling down of the calorimetric cells permitted to envisage a new family of calorimeters, that using the thin suspended membranes as substrate or sample support overcomes the heat capacity addenda problem. In this seminar, we will review the different methods implemented in nanocalorimetry, showing examples, and how the measurement limits have been pushed by the drastic increase in sensitivity.