The term dielectric loss can also be used to describe the charge loss in capacitive structures (memories, transistors...). In those structures, electrons can transit through thin dielectric layers by tunneling, hopping and other trap assisted conduction phenomenon. Those losses become predominant in nanoscale devices. I am not sure how it would apply to rubbery strain sensors though...

I agree with Dr. Rafael, low dielectric loss is important e.g. in cables to reduce heating and to transmit power more efficiently and in electronics, to avoid over-heating. Dielectric heating causes also the increase of ohmic conductivity, which can lead to breakdown in extreme cases. In a microwave oven, however dielectric loss is a "positive" and expected effect.

I understand then, that if we maintain a low tanδ at low voltage, we should not expect to dielectric loss be a determinant parameter in a pressure sensor (apart from heat generation).

Thank you very much for your answers.

Dear Dr. Bartra

Dielectric loss occurs due to lag of polarization with a.c. field. Each type of polarization has different frequency range where loss is effective. In dipolar case it is temperature dependent also. In addition to heat production, dielctric constant also changes when loss occurs in certain frequency range. In some cases, as you mentioned, heat dissipation may be fast and heat production may not be effective but it may not be valid at all frequencies. You have to be careful as dielctric loss is highly frequency dependent. Moreover, in some cases, change in dielectric constant may also be effective for some applications. Effect of dielectric loss on devices is not so simple and highly case sensitive.

Dear Dr. Kumar,

I will select the frequency region taking into account the electric modulus. As you said, in the low region below 15Hz, some electrode polarization is observed (seen in M* graph), while in dielectric spectra, the values of Ɛ' and Ɛ'' can be very large.

Thank you very much for your answer.