Optomechanically induced transparency

Coherent interaction of laser radiation with multilevel atoms and molecules can lead to quantum interference in the electronic excitation pathways. A prominent example observed in atomic three-level-systems is the phenomenon of electromagnetically induced transparency (EIT), in which a control laser induces a narrow spectral transparency window for a weak probe laser beam. The concomitant rapid variation of the refractive index in this spectral window can give rise to dramatic reduction of the group velocity of a propagating pulse of probe light. Dynamic control of EIT via the control laser enables even a complete stop, that is, storage, of probe light pulses in the atomic medium. Here, we demonstrate optomechanically induced transparency (OMIT)--formally equivalent to EIT--in a cavity optomechanical system operating in the resolved sideband regime. A control laser tuned to the lower motional sideband of the cavity resonance induces a dipole-like interaction of optical and mechanical degrees of freedom. Under these conditions, the destructive interference of excitation pathways for an intracavity probe field gives rise to a window of transparency when a two-photon resonance condition is met. As a salient feature of EIT, the power of the control laser determines the width and depth of the probe transparency window. OMIT could therefore provide a new approach for delaying, slowing and storing light pulses in long-lived mechanical excitations of optomechanical systems, whose optical and mechanical properties can be tailored in almost arbitrary ways in the micro- and nano-optomechanical platforms developed to date

Chiral Transparency

Color transparency is the vanishing of initial and final state interactions, predicted by QCD to occur in high momentum transfer quasielastic nuclear reactions. For specific reactions involving nucleons, the initial and final state interactions are expected to be dominated by exchanges of pions. We argue that these interactions are also suppressed in high momentum transfer nuclear quasielastic reactions; this is ``chiral transparency". We show that studies of the $e ^3He \to e'\Delta^{++} nn$ reaction could reveal the influence of chiral transparency.Comment: 20 pages, three figures available by fax from [email protected]; submitted to Phys. Rev.

Water Transparency Protocol

The purpose of this resource is to determine the transparency of water. Students measure water transparency at their undisturbed study site using a transparency tube or Secchi disk. Educational levels: Primary elementary, Intermediate elementary, Middle school, High school

Color Transparency at ELFE

We review the presentations given in the Color Transparency parallel session held during the second ELFE workshop.Comment: Report on the Color Transparency parallel session held during the second ELFE workshop, Saint Malo, France, September 1996, to be published in the Proceedings, N. d'Hose et al ed.(Nuclear Physics A). e-mail: [email protected] and [email protected]

Strategic transparency and electoral pressure

This paper investigates how an office-motivated incumbent can use transparency enhancement on public spending to signal his budgetary management ability and win re-election. We show that when the incumbent faces a popular challenger, transparency policy can be an effective signaling device. A more popular challenger can reduce the probability to enhance transparency, while voters can be better off due to a more informative signaling. It is also shown that a higher level of public interest in fiscal issues can increase the probability of enhancing transparency, while voters can be worse off by a less informative signaling