2025

Anghel, D. V.; Dolineanu, M.; Bergli, J.; Maasilta, I. J.

We theoretically study the heat exchange between electrons and phonons in a thin metallic film embedded in a suspended dielectric membrane, forming a layered structure in a geometry where the thickness of the membrane is much smaller than its width and length, whereas the thickness of the metallic layer is an order of magnitude smaller than the thickness of the membrane. In addition, we concentrate in the low-temperature range, where the dominant acoustic phonon wavelength is comparable to the thickness of the membrane, and where we can use the continuous elasticity theory for the phonon modes (Lamb-wave theory). Here, we extend previous studies to address how the electron-phonon heat power is influenced by the position of the metal film embedded within the insulating part of the membrane, as opposed to it being on top of the membrane. We show that the heat power can be modified by an order of magnitude just by changing the location of the metal film, and the temperature dependence of the heat power can be tuned as well, offering new ways to engineer the heat exchange and heat transport in nanodevices.