"The Critical Casimir Effect and Can One Measure It in a Magnetic Experiment?"Peter Holdsworth

Theory of Quantum Matter Unit would like to invite you to a seminar :

• Date/Time: July 30th (Wed) / 1pm-2pm
• Venue: C015, Lab1
• Title: The Critical Casimir Effect and Can One Measure It in a Magnetic Experiment?
• Speaker: Prof. Peter C.W. Holdsworth
• Affiliation: Ecole Normale Supérieure de Lyon

"The Critical Casimir Effect and Can One Measure It in a Magnetic Experiment?"

Peter C.W. Holdsworth

Ecole Normale Supérieure de Lyon

Confinement of a critical system on the nanoscale leads to the critical Casimir force, whereby truncation of the diverging correlation length gives a singular contribution to the confining forces. The search for experimental realizations of this effect has so far ignored magnetic systems - a surprising fact given that they have long been considered as the　paradigm for studies of criticality  and that the nano-engineering of magnetic thin films is particularly well-advanced. Here we numerically test a new protocol for measurement of the magnetic Casimir force based on the concept of generalized thermodynamic forces. This procedure could be adapted to experiments on magnetic thin films, or to systems as diverse as ferroelectrics, liquid crystals or polymers and could give access to all universality classes including quantum criticality.
By choosing an applied field that opposes magnetic ordering at the boundaries, the Casimir force is found to increase by an order of magnitude over zero field results.

We look forward to seeing many of you !