Information erasure without an energy cost
Joan A. Vaccaro1,2,* and Stephen M. Barnett2
-Author Affiliations
1Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia
2Department of Physics, SUPA, University of Strathclyde, Glasgow G4 ONG, UK
*Author for correspondence (j.a.vaccaro@griffith.edu.au).
Abstract
Landauer argued that the process of erasing the information stored in a memory device incurs an energy cost in the form of a minimum amount of mechanical work. We find, however, that this energy cost can be reduced to zero by paying a cost in angular momentum or any other conserved quantity. Erasing the memory of Maxwell’s demon in this way implies that work can be extracted from a single thermal reservoir at a cost of angular momentum and an increase in total entropy. The implications of this for the second law of thermodynamics are assessed.
information erasure, thermodynamics, canonical ensemble, spin system
Received November 4, 2010.
Accepted December 15, 2010.
This journal is © 2011 The Royal Society
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