How to Measure Entropy of Exotic Particles

by Yigal Meir

BGU

at Physics Colloquium

Tue, 18 Mar 2025, 12:00
Ilse Katz Institute for Nanoscale Science & Technology (51), room 015

Abstract

In recent years many candidate setups have been proposed to support exotic quasi-particles, such as Majorana fermions (MFs), which may be relevant for quantum computing, but whether these particles have been observed experimentally is currently a topic of a vivid debate. Entropy measurements can unambiguously separate these quasi-particles from other, simpler excitations. The entropy of a MF is, for example, log2/2 (in units of the Boltzman constant), a fractional value that cannot be attributed to a localized excitation. However, standard entropy measurements applicable to bulk systems cannot be utilized in measuring the additional entropy of a mesoscopic device, which may be due to less than a single electron in the device. In this talk I will describe recent theoretical and experimental progress in performing such measurements, either using thermopower and/or using the Maxwell relations. Particular examples will be single and double quantum dots in the Coulomb blockade regime. Lastly I will discuss the back action of the measuring device on the system, and how one can use that to generate novel exotic systems.

*** Refreshments at 12:00, talk at 12:15.

Created on 09-03-2025 by Kats, Yevgeny (katsye)
Updaded on 11-03-2025 by Kats, Yevgeny (katsye)