1.

Record Nr.

UNINA9910373931703321

Autore

Shastry Abhay

Titolo

Theory of Thermodynamic Measurements of Quantum Systems Far from Equilibrium / / by Abhay Shastry

Pubbl/distr/stampa

Cham : , : Springer International Publishing : , : Imprint : Springer, , 2019

ISBN

3-030-33574-7

Edizione

[1st ed. 2019.]

Descrizione fisica

1 online resource (152 pages)

Collana

Springer Theses, Recognizing Outstanding Ph.D. Research, , 2190-5053

Disciplina

530.12011

Soggetti

Quantum theory

Thermodynamics

Chemistry, Physical and theoretical

Mathematical physics

Spectrum analysis

Microscopy

Quantum Physics

Physical Chemistry

Mathematical Physics

Spectroscopy and Microscopy

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Nota di bibliografia

Includes bibliographical references.

Nota di contenuto

Chapter1. Introduction -- Chapter2. Temperature and Voltage -- Chapter3. Coldest Measurable Temperature -- Chapter4. STM as a Thermometer -- Chapter5. Entropy -- Chapter6. Concluding Remarks.

Sommario/riassunto

This thesis presents several related advances in the field of nonequilibrium quantum thermodynamics. The central result is an ingenious proof that the local temperature and voltage measurement in a nonequilibrium system of fermions exists and is unique, placing the concept of local temperature on a rigorous mathematical footing for the first time. As an intermediate step, a proof of the positivity of the Onsager matrix of linear response theory is given -- a statement of the second law of thermodynamics that had lacked an independent proof for 85 years. A new experimental method to measure the local



temperature of an electron system using purely electrical techniques is also proposed, which could enable improvements to the spatial resolution of thermometry by several orders of magnitude. Finally, a new mathematically-exact definition for the local entropy of a quantum system in a nonequilibrium steady state is derived. Several different measures of the local entropy are discussed, relating to the thermodynamics of processes that a local observer with varying degrees of information about the microstates of the system could carry out, and it is shown that they satisfy a hierarchy of inequalities. Proofs of the third law of thermodynamics for generic open quantum systems are presented, taking into account the entropic contribution due to localized states. Appropriately normalized (per-state) local entropies are defined and are used to quantify the departure from local equilibrium.