NCTS (South) DATE 2015-03-11 TIME 14:00 PLACE R49223, Second Physics Building , NCKU FIELD Other SPEAKER Dr. Jun Yonggun - Department of Physics, University of California, San Diego,USA TITLE High-Precision Test of Landauer’s Principle in a Feedback Trap ABSTRACT Landauer's principle states that an irreversible logical operation such as memory erasure must dissipate heat, no matter how slowly it is performed. For example, to reset to one" a memory that can be in state 0 or 1 requires at least $kT\ln2$ of work. We experimentally tested the validity of Landauer's principle using a feedback trap. A colloidal particle is placed in a time-dependent, "virtual" double-well potential created by a feedback trap. We found that the work required to reduce the number of possible system states by a factor of two gradually approaches to $kT\ln2$ as the processing time increases. In a control experiment, similar manipulations that do not reduce the number of system states require no work when done infinitely slowly. Our results are compatible with the Jarzynski relation for nonequilibrium systems.