Landauer vs. Nernst: What is the True Cost of Cooling a Quantum System?

Understand

Thermodynamics connects our knowledge of the world to our capability to manipulate and thus to control it.

• This crucial role of control is exemplified by the third law of thermodynamics, Nernst's unattainability principle, which states that infinite resources are required to cool a system to absolute zero temperature.
• But what are these resources and how should they be utilized? And how does this relate to Landauer's principle that famously connects information and thermodynamics? We answer these questions by providing a framework for identifying the resources that enable the creation of pure quantum states.
• We show that perfect cooling is possible with Landauer energy cost given infinite time or control complexity.