Nonlinearity in Single Photon Detection: Modeling and Quantum Tomography

Single Photon Detectors are integral to quantum optics and quantum information. Superconducting Nanowire based detectors exhibit new levels of performance, but have no accepted quantum optical model that is valid for multiple input photons. By performing Detector Tomography, we improve the recently proposed model [M.K. Akhlaghi and A.H. Majedi, IEEE Trans. Appl. Supercond. 19, 361 (2009)] and also investigate the manner in which these detectors respond nonlinearly to light, a valuable feature for some applications. We develop a device independent model for Single Photon Detectors that incorporates this nonlinearity

Perbedaan Efektivitas Penambahan Bubuk Cangkang Telur Ayam Ras dengan Ayam Kampung terhadap Durasi Perdarahan (In Vivo)

Latar belakang : Kandungan terbesar pada cangkang telur ayam ras dan adalah kalsium. Kalsium sangat berperan dalam proses hemostasis. Cangkang telur yang selama ini hanya sebagai bahan yang dibuang akan dimanfaatkan untuk mengurangi limbah. Tujuan : Penelitian ini bertujuan untuk mengetahui efektivitas antara pemberian bubuk cangkang telur ayam ras dengan ayam kampung terhadap durasi perdarahan pada ekor tikusRattus norvegicus. Metode : Rattus norvegicus jantan umur 3 bulan, berat 150-200 gr diberikan perlukaan padaekornya sepanjang 1cm, kedalaman 0,1 cm dengan blade dan diberikan penambahan bubuk cangkang telur ayam ras atau kampung pada daerah bekas sayatan, kemudian dihitung durasi perdarahannya. Hasil : Rata-rata durasi perdarahan pada kelmpok penambahan bubuk cangkang telur ayam ras yaitu 5,471 menit, ayam kampung 8,096 menit sedangkan adalah tanpa perlakuan 12,234 menit. Uji analitik dengan menggunakan one way Anova α=0,05 diperoleh P=0,000 yang berarti ada pengaruh penambahan bubuk cangkang telur ayam ras dan ayam kampung terhadap durasi perdarahan pada ekor tikus Rattus norvegicus. Kesimpulan : Kesimpulan penelitian ini adalah bubuk cangkang telur ayam ras dan ayam kampung berpengaruh terhadap durasi perdarahan dan bubuk cangkang telur ayam ras yang paling cepat menghentikan perdarahan

Human monoclonal antibodies against Ross River virus target epitopes within the E2 protein and protect against disease

Ross River fever is a mosquito-transmitted viral disease that is endemic to Australia and the surrounding Pacific Islands. Ross River virus (RRV) belongs to the arthritogenic group of alphaviruses, which largely cause disease characterized by debilitating polyarthritis, rash, and fever. There is no specific treatment or licensed vaccine available, and the mechanisms of protective humoral immunity in humans are poorly understood. Here, we describe naturally occurring human mAbs specific to RRV, isolated from subjects with a prior natural infection. These mAbs potently neutralize RRV infectivity in cell culture and block infection through multiple mechanisms, including prevention of viral attachment, entry, and fusion. Some of the most potently neutralizing mAbs inhibited binding of RRV to Mxra8, a recently discovered alpahvirus receptor. Epitope mapping studies identified the A and B domains of the RRV E2 protein as the major antigenic sites for the human neutralizing antibody response. In experiments in mice, these mAbs were protective against cinical disease and reduced viral burden in multiple tissues, suggesting a potential therapeutic use for humans

Controlling a superconducting nanowire single-photon detector using tailored bright illumination

We experimentally demonstrate that a superconducting nanowire single-photon detector is deterministically controllable by bright illumination. We found that bright light can temporarily make a large fraction of the nanowire length normally-conductive, can extend deadtime after a normal photon detection, and can cause a hotspot formation during the deadtime with a highly nonlinear sensitivity. In result, although based on different physics, the superconducting detector turns out to be controllable by virtually the same techniques as avalanche photodiode detectors. As demonstrated earlier, when such detectors are used in a quantum key distribution system, this allows an eavesdropper to launch a detector control attack to capture the full secret key without being revealed by to many errors in the key.Comment: Expanded discussions, updated references. 9 pages, 8 figure

A Single-Photon Imager Based on Microwave Plasmonic Superconducting Nanowire

Detecting spatial and temporal information of individual photons by using single-photon-detector (SPD) arrays is critical to applications in spectroscopy, communication, biological imaging, astronomical observation, and quantum-information processing. Among the current SPDs1,detectors based on superconducting nanowires have outstanding performance2, but are limited in their ability to be integrated into large scale arrays due to the engineering difficulty of high-bandwidth cryogenic electronic readout3-8. Here, we address this problem by demonstrating a scalable single-photon imager using a single continuous photon-sensitive superconducting nanowire microwave-plasmon transmission line. By appropriately designing the nanowire's local electromagnetic environment so that the nanowire guides microwave plasmons, the propagating voltages signals generated by a photon-detection event were slowed down to ~ 2% of the speed of light. As a result, the time difference between arrivals of the signals at the two ends of the nanowire naturally encoded the position and time of absorption of the photon. Thus, with only two readout lines, we demonstrated that a 19.7-mm-long nanowire meandered across an area of 286 {\mu}m * 193 {\mu}m was capable of resolving ~590 effective pixels while simultaneously recording the arrival times of photons with a temporal resolution of 50 ps. The nanowire imager presents a scalable approach to realizing high-resolution photon imaging in time and space