Channelization architecture for wide-band slow light in atomic vapors

We propose a ``channelization'' architecture to achieve wide-band electromagnetically induced transparency (EIT) and ultra-slow light propagation in atomic Rb-87 vapors. EIT and slow light are achieved by shining a strong, resonant ``pump'' laser on the atomic medium, which allows slow and unattenuated propagation of a weaker ``signal'' beam, but only when a two-photon resonance condition is satisfied. Our wideband architecture is accomplished by dispersing a wideband signal spatially, transverse to the propagation direction, prior to entering the atomic cell. When particular Zeeman sub-levels are used in the EIT system, then one can introduce a magnetic field with a linear gradient such that the two-photon resonance condition is satisfied for each individual frequency component. Because slow light is a group velocity effect, utilizing differential phase shifts across the spectrum of a light pulse, one must then introduce a slight mismatch from perfect resonance to induce a delay. We present a model which accounts for diffusion of the atoms in the varying magnetic field as well as interaction with levels outside the ideal three-level system on which EIT is based. We find the maximum delay-bandwidth product decreases with bandwidth, and that delay-bandwidth product ~1 should be achievable with bandwidth ~50 MHz (~5 ns delay). This is a large improvement over the ~1 MHz bandwidths in conventional slow light systems and could be of use in signal processing applications.Comment: Published in SPIE Proceedings, Photonics West 2005 (San Jose, CA, Jan. 22-27, 2005

Lead Us Not Into Translation: Notes Toward a Theoretical Foundation for Asian Studies

I begin this work with a simple question. Why is it impossible to imagine, much less write, a work like Michel Foucault's Discipline and Punish within Asian area studies? The impossibility I am referring to is not of content but of form. It is not just about writing such a text but about having it read as something more than a description; having it read for its theoretical significance more generally. That is to say, it is about the impossibility of writing a work that is principally of a theoretical nature but that is empirically and geographically grounded in Asia rather than in Europe or America. Why is it that, when it comes to Asian area studies, whenever “theory” is invoked, it is invariably understood to mean “applied theory” and assumed to be of value only insofar as it helps tell the story of the “real” in a more compelling way? To some extent, what follows is an attempt to explain historically how Western area studies on Asia came to appreciate theory in this limited and limiting way. At the same time, as I began to investigate the history and prehistory of this diaphanous field, I began to recognize the possibilities of a very different form of area studies that could have emerged had different sets of pressures pushed it in a slightly different direction. This essay is therefore an attempt to recuperate these now forgotten possibilities and to build on them in order to produce a different way of seeing, writing, and theorizing Asian area studies

The Square: A Political Anthropology of the Built Environment

Beginning in Tian'anmen Square at dawn, this paper traces the political cosmologies of China through the built environment of Beijing. The diagnostic value of the built environment is revealed in its ability to help us navigate through the history of various political cosmologies that have informed the building and rebuilding of this city. From dynastic times when Celestial power was driven by the flow of 'qi' though the 'toppling' of the city axis and the imposition of another socialist cosmology and then onto the phantasmagoric showpieces of the economic miracle, the built environment becomes an archeological site of politics, revealing a way of seeing politics that is ethnographic and concerned with the everyday

Observation of Quantum Shock Waves Created with Ultra Compressed Slow Light Pulses in a Bose-Einstein Condensate

We have used an extension of our slow light technique to provide a method for inducing small density defects in a Bose-Einstein condensate. These sub-resolution, micron-sized defects evolve into large amplitude sound waves. We present an experimental observation and theoretical investigation of the resulting breakdown of superfluidity. We observe directly the decay of the narrow density defects into solitons, the onset of the `snake' instability, and the subsequent nucleation of vortices.Comment: 15 pages, 5 figure

Preliminary Geologic Description Mobil Producing G.E. Cargill No.14

Two intervals of the Travis Peak Formation were cored in the Mobil Producing Cargill No. 14 well, Waskom field, Harrison County, Texas. Core was recovered from 5,903.0 to 5,960.4 ft and from 6,148.0 to 6,297.1 ft. The top of the Travis Peak is at 5,901 ft (log depth), so the core begins close to the top of the formation.Bureau of Economic Geolog

Detecting changes to sub-diffraction objects with quantum-optimal speed and accuracy

Detecting if and when objects change is difficult in passive sub-diffraction imaging of dynamic scenes. We consider the best possible tradeoff between responsivity and accuracy for detecting a change from one arbitrary object model to another in the context of sub-diffraction incoherent imaging. We analytically evaluate the best possible average latency, for a fixed false alarm rate, optimizing over all physically allowed measurements of the optical field collected by a finite 2D aperture. We find that direct focal-plane detection of the incident optical intensity achieves sub-optimal detection latencies compared to the best possible average latency, but that a three-mode spatial-mode demultiplexing measurement in concert with on-line statistical processing using the well-known CUSUM algorithm achieves this quantum limit for sub-diffraction objects. We verify these results via Monte Carlo simulation of the change detection procedure and quantify a growing gap between the conventional and quantum-optimal receivers as the objects are more and more diffraction-limited.Comment: 4 pages, 3 figure

Lead Us Not into Translation: Notes Toward a Theoretical Foundation for Asian Studies

I begin this work with a simple question. Why is it impossible to imagine, much less write, a work like Michel Foucault’s Discipline and Punish within Asian area studies? The impossibility I am referring to is not of content but of form. It is not just about writing such a text but about having it read as something more than a description; having it read for its theoretical significance more generally. That is to say, it is about the impossibility of writing a work that is principally of a theoretical nature but that is empirically and geographically grounded in Asia rather than in Europe or America. Why is it that, when it comes to Asian area studies, whenever “theory” is invoked, it is invariably understood to mean “applied theory” and assumed to be of value only insofar as it helps tell the story of the “real” in a more compelling way? To some extent, what follows is an attempt to explain historically how Western area studies on Asia came to appreciate theory in this limited and limiting way. At the same time, as I began to investigate the history and prehistory of this diaphanous field, I began to recognize the possibilities of a very different form of area studies that could have emerged had different sets of pressures pushed it in a slightly different direction. This essay is therefore an attempt to recuperate these now forgotten possibilities and to build on them in order to produce a different way of seeing, writing, and theorizing Asian area studies.Je commence cet article par une simple question. Pourquoi est-il impossible d’imaginer, encore moins d’écrire, une œuvre comme Surveiller et Punir au sein des Etudes asiatiques ? L’impossibilité à laquelle je me réfère n’est pas liée au fond mais à la forme. Il ne s’agit pas seulement d’écrire un tel texte mais de le faire lire comme quelque chose qui soit plus qu’une description ; le faire lire aussi pour sa portée théorique. Il s’agit de l’impossibilité d’écrire une œuvre qui serait de nature essentiellement théorique mais qui, empiriquement et géographiquement, serait basée en Asie plutôt qu’en Europe ou en Amérique. Pourquoi donc la théorie, lorsqu’il s’agit des Etudes asiatiques, est invariablement comprise comme une « théorie appliquée » dont la valeur ajoutée repose sur sa capacité à raconter l’histoire du « réel » d’une manière plus convaincante ?Dans une certaine mesure, ce qui suit est une tentative pour expliquer historiquement comment, en Occident, les Area studies sur l’Asie en sont venues à comprendre la théorie de cette manière limitée et limitative. En même temps, lorsque j’ai commencé à étudier l’histoire et la préhistoire de ce champ diaphane, j’ai pu apercevoir les possibilités d’une forme très différente d’études régionales qui auraient pu émerger si différents ensembles de pressions l’avait poussée dans une direction légèrement différente. Cet essai est donc une tentative pour récupérer ces possibilités désormais oubliées et construire, sur ces bases, une autre manière de voir, écrire et théoriser les Etudes asiatiques

Cultural Revolution as Method

This paper treats the Chinese Cultural Revolution as a means by which to open on to a more affective approach to the question of the political. It examines one piece of art-technology of that period and shows the way it intuitively worked within the fluidity of power to produce political intensity. This one technology is a microcosm of the Cultural Revolution notion of the political that was built around an attempt to channel and harness affective power towards revolutionary ends. Both because it attempts to direct the political through the affective dimension and because its methods of doing so resembled contemporary art practices, this paper opens on to the possibilities of a method based on an art rather than a science of the political