We write down a maximally supersymmetric one parameter deformation of the field theory action of Bagger and Lambert. We show that this theory on R × T 2 is invariant under the superalgebra of the maximally supersymmetric Type IIB plane wave. It is argued that this theory holographically describes the Type IIB plane wave in the discrete light-cone quantization (DLCQ). 04/2008a jgomis@perimeterinstitute.ca b ajafarisalim@perimeterinstitute.ca c fpasserini@perimeterinstitute.ca

Circuits using superconducting single-photon detectors and Josephson junctions to perform signal reception, synaptic weighting, and integration are investigated. The circuits convert photondetection events into flux quanta, the number of which is determined by the synaptic weight. The current from many synaptic connections is inductively coupled to a superconducting loop that implements the neuronal threshold operation. Designs are presented for synapses and neurons that perform integration as well as detect coincidence events for temporal coding. Both excitatory and inhibitory connections are demonstrated. It is shown that a neuron with a single integration loop can receive input from 1000 such synaptic connections, and neurons of similar design could employ many loops for dendritic processing.

Superconducting nanowire single photon detectors (SNSPDs) are fabricated directly on diamond substrates and their optical and electrical properties are characterized. Dark count performance and photon count rates are measured at varying temperatures for 1310nm and 632nm photons. The procedure to prepare diamond substrate surfaces suitable for the deposition and patterning of thin film superconducting layers is reported. Using this approach, diamond substrates with less than 300pm RMS surface roughness are obtained.Diamond has recently gained significant interest as a promising platform for on-chip high-performance photonic devices [1][2][3]. Diamond exhibits many favorable material properties such as a high refractive index (n=2.4), wide bandgap (5.5eV), and a large optical transmission range from the UV to the mid infrared. Diamond is also host to numerous defect color centers such as the nitrogen-vancancy (NV) center, that can be utilized as an optically addressable spin based memory, particularly interesting in the field of quantum information processing [4,5]. In addition, diamond has a relatively large Kerr non-linearity [6] (n 2 = 1.3 · 10 −19 m 2 /W) making it an attractive platform for on-chip nonlinear optics in the visible and infrared wavelengths [7]. An exciting application for utilizing this diamond non-linearity could allow for frequency conversion of photons generated by color centers in diamond, which typically emit in the visible range, to the telecom wavelengths [8]. This could enable transmission of quantum information and distribution of quantum entanglement [9, 10] over long distances, for the realization of quantum repeaters. Such an integrated diamond quantum photonics platform would benefit from the realization of high performance single photon detectors, with broadband photon sensitivity, that are integrated directly on the same diamond chip.Superconducting nanowire single photon detectors (SNSPDs) outperform other single photon detector technologies on several merits such as quantum efficiency [11], timing jitter, dark count rates, and broad spectral sensitivity [12,13]. SNSPDs typically consist of narrow width nanowires patterned into an ultrathin (4nm to 8nm) superconducting film, commonly made from niobium nitride or some derivative of [14]. The nanowires are current biased close to the critical current of the superconductor. When an incident photon is absorbed by the wire, a small resistive hotspot is formed generating a voltage pulse that can be subsequently amplified and measured [15]. Since the performance of SNSPDs is critically * loncar@seas.harvard.edu dependent on nanowire structural uniformity, it is crucial to have them deposited on smooth substrate surfaces to avoid constrictions that can have detrimental effects on detection efficiency [16].In this letter, we report NbTiN superconducting nanowires deposited directly on diamond substrates that exhibit promising single photon sensitivity. Specifically, we provide details of the fabrication procedure developed, resulting in ...

The Adler-Bell-Jackiw (ABJ) anomaly of a 3 + 1 dimensional QED is calculated in the presence of a strong magnetic field. It is shown that in the regime with the lowest Landau level (LLL) dominance a dimensional reduction from D = 4 to D = 2 dimensions occurs in the longitudinal sector of the low energy effective field theory. In the chiral limit, the resulting anomaly is therefore comparable with the axial anomaly of a two dimensional massless Schwinger model. It is further shown that the U A (1) anomaly of QED in a strong magnetic field is closely related to the nonplanar axial anomaly of a conventional noncommutative U (1) gauge theory.

In this paper, we theoretically show that a multi-layer superconducting nanowire single-photon detector (SNSPD) is capable of approaching characteristics of an ideal SNSPD in terms of the quantum efficiency, dark count, and band-width. A multi-layer structure improves the performance in two ways. First, the potential barrier for thermally activated vortex crossing, which is the major source of dark counts and the reduction of the critical current in SNSPDs is elevated. In a multi-layer SNSPD, a vortex is made of 2D-pancake vortices that form a stack. It will be shown that the stack of pancake vortices effectively experiences a larger potential barrier compared to a vortex in a single-layer SNSPD. This leads to an increase in the experimental critical current as well as significant decrease in the dark count rate. In consequence, an increase in the quantum efficiency for photons of the same energy or an increase in the sensitivity to photons of lower energy is achieved. Second, a multi-layer structure improves the efficiency of single-photon absorption by increasing the effective optical thickness without compromising the single-photon sensitivity.