Control of coherent backscattering of light by breaking optical reciprocity

Seminar
Speaker
Dr. Yaron Bromberg
Date
25/11/2015 - 14:00Add to Calendar 2015-11-25 14:00:00 2015-11-25 14:00:00 Control of coherent backscattering of light by breaking optical reciprocity Reciprocity is a universal principle that has a profound impact on many areas of physics.  A fundamental phenomenon in condensed-matter physics, optical physics and acoustics, arising from reciprocity, is the constructive interference of waves which propagate along time-reversed paths in disordered media, leading to, for example, weak localization and the metal-insulator transition. Previous studies have shown that such coherent effects are suppressed when reciprocity is broken. In my talk I will present our recent experiment, in which we have shown that by tuning a non-reciprocal phase we can coherently control weak localization of light, also known as coherent backscattering, rather than simply suppress it [1]. By utilizing a magneto-optical effect, we controlled the interference between time-reversed paths inside a multimode fiber with strong mode mixing, observed for the first time the optical analogue of weak anti-localization, and realized a continuous transition from weak localization to anti-localization. In the last part of the talk I will show how we can utilize the subtle interplay between reciprocity and mode mixing in multimode fibers for secure optical communication [2].   [1] Y. Bromberg, B. Redding, S. M. Popoff, and H. Cao, Control of coherent backscattering by breaking optical reciprocity, arXiv:1505.01507. [2] Y. Bromberg, B. Redding, S. M. Popoff, and H. Cao, Remote key establishment by mode mixing in multimode fibers and optical reciprocity, arXiv:1506.07892. seminar room on the 9th floor of the nano building המחלקה לפיזיקה physics.dept@mail.biu.ac.il Asia/Jerusalem public
Place
seminar room on the 9th floor of the nano building
Abstract

Reciprocity is a universal principle that has a profound impact on
many areas of physics.  A fundamental phenomenon in condensed-matter
physics, optical physics and acoustics, arising from reciprocity, is
the constructive interference of waves which propagate along
time-reversed paths in disordered media, leading to, for example, weak
localization and the metal-insulator transition. Previous studies have
shown that such coherent effects are suppressed when reciprocity is
broken. In my talk I will present our recent experiment, in which we
have shown that by tuning a non-reciprocal phase we can coherently
control weak localization of light, also known as coherent
backscattering, rather than simply suppress it [1]. By utilizing a
magneto-optical effect, we controlled the interference between
time-reversed paths inside a multimode fiber with strong mode mixing,
observed for the first time the optical analogue of weak
anti-localization, and realized a continuous transition from weak
localization to anti-localization. In the last part of the talk I will
show how we can utilize the subtle interplay between reciprocity and
mode mixing in multimode fibers for secure optical communication [2].

 

[1] Y. Bromberg, B. Redding, S. M. Popoff, and H. Cao, Control of
coherent backscattering by breaking optical reciprocity,
arXiv:1505.01507.
[2] Y. Bromberg, B. Redding, S. M. Popoff, and H. Cao, Remote key
establishment by mode mixing in multimode fibers and optical
reciprocity, arXiv:1506.07892.

תאריך עדכון אחרון : 16/11/2015