Europhys. Lett.
Volume 67, Number 4, August 2004
Page(s) 559 - 564
Section General
Published online 01 August 2004
Europhys. Lett., 67 (4), pp. 559-564 (2004)
DOI: 10.1209/epl/i2004-10094-8

Nonreciprocity and the second law of thermodynamics: An exact relation for nonlinear media

O. Narayan1 and A. Dhar2

1  Department of Physics, University of California - Santa Cruz, CA 95064, USA
2  Raman Research Institute - Bangalore 560080, India

(Received 5 April 2004; accepted in final form 7 June 2004)

Applying monochromatic filters to the ends of a one-dimensional nonlinear medium, we find an exact identity relating the nonreciprocity -the difference in transmission from the left or right- to the power flowing with equal sources on both sides. Thus, nonreciprocity has an unanticipated link to an apparent violation of the second law of thermodynamics; this violation is only apparent because of a subtle dependence on the (arbitrarily small) filter bandwidth. At high intensities, a nonperturbative transition to a noisy state destroys the identity. Apart from the theoretical insight provided by filters, not contaminating other frequency channels has obvious advantages in communications.

05.45.-a - Nonlinear dynamics and nonlinear dynamical systems.
43.25.+y - Nonlinear acoustics.
42.65.Sf - Dynamics of nonlinear optical systems; optical instabilities, optical chaos and complexity, and optical spatio-temporal dynamics.

© EDP Sciences 2004