Theory of disorder-induced multiple coherent scattering in photonic crystal waveguides

We introduce a theoretical formalism to describe disorder-induced extrinsic scattering in slow-light photonic crystal waveguides. This work details and extends the optical scattering theory used in a recent \emph{Physical Review Letter} [M. Patterson \emph{et al.}, \emph{Phys. Rev. Lett.} \textbf{102}, 103901 (2009)] to describe coherent scattering phenomena and successfully explain complex experimental measurements. Our presented theory, that combines Green function and coupled mode methods, allows one to self-consistently account for arbitrary multiple scattering for the propagating electric field and recover experimental features such as resonances near the band edge. The technique is fully three-dimensional and can calculate the effects of disorder on the propagating field over thousands of unit cells. As an application of this theory, we explore various sample lengths and disordered instances, and demonstrate the profound effect of multiple scattering in the waveguide transmission. The spectra yield rich features associated with disorder-induced localization and multiple scattering, which are shown to be exasperated in the slow light propagation regime

The Trent Affair: Avoiding a Possible Crisis during the Civil War

In November 1861, Union Naval Captain Charles Wilkes seized the Trent, a British mailing ship, because it was transporting two Confederate diplomats, John Slidell and James Mason. Wilkes captured the two Confederate representatives due to what he considered were treasonous actions against the Union, but he did so without any orders from the Union government. Under a proclamation issued by the Queen of Britain at the start of the Civil War, Britain recognized the Confederacy as a belligerent and was not supposed to transport the dispatches of Slidell and Mason because international law considered them contraband. Yet, by acknowledging the Confederacy as belligerent, Britain stated that the Union and the Confederacy would be given equal treatment in British ports. Confederate ships could obtain necessary supplies from British ports to aid them in fighting Union ships. Northerners expected British support and were dismayed by the British acknowledgement of the Confederacy. The Trent Affair escalated the already unpopular opinion towards Britain held by the Union public due to the Queen’s Proclamation. The Union publicly celebrated the actions of Wilkes as the first naval success against the Confederacy. Newspapers depicted the British as trying to take away the victory and, as a result, helping facilitate negotiations with the Confederates. Union citizens did not want to concede to British demands to give up the rebels. Northerners felt that if Britain wanted to go to war over the Trent Affair, then they would mobilize for such a conflict. The Lincoln administration did not want to give any indication to the Confederacy that the British could have their way with the Union, for that would just inspire the Confederacy to strive for British support. President Lincoln dealt with the public pressure, while also receiving correspondence from government officials. However, the advice Lincoln received urged him to concede to Britain’s demands, which went against the public’s wish to fight Britain. By adhering to British demands concerning the Trent Affair, Lincoln sacrificed public opinion for his decision to maintain peaceful relations with Britain. Lincoln had the greater goal of reunifying the United States and he did not want to hinder reunification by expanding the war internationally

Face to Face in Ireland

While still in the midst of their study abroad experiences, students at Linfield College write reflective essays. Their essays address issues of cultural similarity and difference, compare lifestyles, mores, norms, and habits between their host countries and home, and examine changes in perceptions about their host countries and the United States. In this essay, Brenna Patterson describes her observations during her study abroad program at the National University of Ireland in Galway

Connecting Ethics to Action: An Introduction to Ethical Decision Making

A patron calls the Circulation Desk late in the evening and gets a student worker.The patron wants to know what their roommate checked out so they can be sure to return all of the materials. The student gives the information, trying to be helpful to the patron.The patron comes in the next morning very upset because his privacy has been violated and threatening a lawsuit. The student worker defends his actions, saying he was trying to give excellent customer service, just as he learned in the orientation manual. How does one calm the patron, educate the student worker, and otherwise deal with this, and other, ethical dilemmas? This article proposes the use of, and training in, Ethical Decision Making to assist in alleviating ethical dilemmas. This article will describe Ethical Decision Making, or EDM, and will offer a brief background on the field of EDM. The article will also be of practical use by providing ways libraries and librarians can use EDM, presenting a model of EDM, and suggesting ways to implement and train in EDM

Outside the Box: A New Perspective on Operation Windsor—The Rationale Behind the Attack on Carpiquet, 4 July 1944

Operation Windsor never seemed to fit. Why, one asks, would the 3rd Canadian Infantry Division launch a major operation to seize Carpiquet village and airfield a mere four days before I British Corps started the much larger three-division Operation Charnwood to seize Caen? It seemed a distraction from the main effort—a needless diversion of resources. This view was reinforced by the standard interpretations of the battles as reflected in the two introductory quotations: Windsor as a prelude to Charnwood. I had succumbed to what I will call the black box syndrome. I looked only within the analytical framework established by countless historians from C.P. Stacey to Terry Copp3 to John A. English, and, like them, saw Operation Windsor as a precursor to Operation Charnwood. It was upon visiting the battlefield in 1997 and 1998 with the Canadian Battlefields Foundation student study tour that I gained a more complete understanding of the battle. For it is only on the field itself that one can understand that Operation Windsor had very little to do with Operation Charnwood, and so much more to do with Operations Epsom and Jupiter. Epsom is familiar to any scholar of the campaign, but Operation Jupiter, the 43rd Wessex Division attack on Hill 112, is more obscure. It was the ground that showed me the link which was reinforced by a close review of the I British Corps operations log. In this article I will try and show that the traditional interpretation of Operation Windsor has suffered from a “Canada-centric” bias that fails to relate the ground to the battle and assumes that all that precedes Charnwood must be setting the stage for that battle. First a review of the traditional interpretation is required