Integration of Advanced Optics for Trapped Ion Quantum Information Processing

<p>Trapped ion systems are the leading candidate for quantum information processing because many of the critical components have already been demonstrated. Scaling trapped ion systems to large numbers of ions is currently believed possible, but much work remains to prove it. Microfabricated surface ion traps are increasing in popularity for their ease of mass production and their ability to manipulate individual ions and interact arbitrary pairs of ions. Even with the advent of scalable ion traps, detection of an individual ion trapped in a high vacuum poses a challenge. The internal state of the ion chosen for a quantum bit can be measured via exposure to a probe beam that causes one state to scatter light (a "bright" state), but not the other state (a "dark" state). In free space, a single ion acts like a point source that emits in all directions; a standard two inch lens system can only collect about 2% of the light emitted by the ion. Poor light collection results in a high error rate and slow determination of the internal state of the ion. Fast, high fidelity state detection is necessary for quantum error correction and loophole-free Bell experiments at short (less than 100\,km) distances, and high efficiency collection is necessary to rapidly interconnect separate quantum computers. We demonstrate state detection fidelities of 99%, 99.856(8)% and 99.915(7) % which correspond to detection times of 10.5, 28.1 and 99.8 us, respectively.</p>Dissertatio

Multi-scale Optics for Enhanced Light Collection from a Point Source

High efficiency collection of photons emitted by a point source over a wide field-of-view (FoV) is crucial for many applications. Multi-scale optics over improved light collection by utilizing small optical components placed close to the optical source, while maintaining a wide FoV provided by conventional imaging optics. In this work, we demonstrate collection efficiency of 26% of photons emitted by a point-like source using a micromirror fabricated in silicon with no significant decrease in collection efficiency over a 10 mm object space.Comment: 4 pages, 4 figure

Studi Analitis dan Eksperimental Mekanisme Slip-Kritis Sambungan Struktural Baut Baja

Letak geografis Indonesia menjadikan Indonesia sebagai negara yang rawan bencana gempa baik tektonik maupun vulkanik. Standar Nasional Indonesia (SNI) 1729:2015 mensyaratkan sambungan baut bangunan baja dengan tinggi lebih dari 38 m, harus menggunakan baut mutu tinggi (High Strength Bolt – HSB) dengan pra-tarik. Sambungan baut kencang pas (snug tight) dan sambungan baut dengan pra-tarik, secara kasat mata tidak berbeda. Perbedaan akan terjadi saat sambungan dibebani yaitu untuk sambungan dengan pra-tarik, slip antar pelat yang disambung sebagai akibat ukuran lubang baut yang lebih besar dari diameter baut baru akan terjadi saat kuat batas slip terlampaui. Penelitian ini bermaksud mengamati kekuatan dan perilaku sambungan baut dengan pra-tarik terhadap peningkatan beban. Analisis dilakukan menurut SNI 1729:2015, validasi data melalui uji eksperimental menggunakan benda uji pelat BJ37 yang dibebani aksial tarik konsentris. Sambungan menggunakan HSB-A325 M12, lubang standar dengan persiapan permukaan kelas A. Pemberian pra-tarik baut dengan cara putar mur (turn-of-nut). Hasil pengujian menunjukan kuat batas slip (Pslip) 37,998 kN, nilai ini 5,7% lebih tinggi dibanding hasil analitis sebesar 35,94 kN. Setelah tercapai kuat batas slip, sambungan tetap dapat menerima pembebanan dengan mekanisme pengalihan gaya tumpu dan mencapai kuat batas sambungan (Pu) sebesar 50,197 kN, yang berarti masih dapat menerima peningkatan beban 32% setelah slip terjadi. Putar mur (turn-of-nut) salah satu metode yang direkomendasikan SNI 1729:2015, merupakan cara yang cukup sederhana untuk pemberian pra-tarik karena tidak diperlukan alat khusus dan gaya pra-tarik minimum yang disyaratkan dapat dipenuhi dengan tercapainya Pslip hasil eksperimen tidak lebih rendah dibandingkan dengan hasil analisi

Studi Eksperimental dan ANalitis Sambungan Batang Tarik Tipe Kegagalan Geser Baut

Sambungan baut pada batang tarik baja memiliki kapasitas dengan macam-macam tipe kegagalan. Kapasitas sambungan baut pada batang tarik baja dapat ditentukan melalui analisis kapasitas dan kegagalan sambungan. Pada analisis kapasitas dan kegagalan sambungan batang tarik baja, kapasitas sambungan batang tarik baja yang ditentukan dihasilkan berdasarkan banyak parameter struktur diantaranya profil dan mutu batang tarik, tebal dan mutu pelat penyambung, dan juga tebal dan mutu baut sambungan. Kapasitas sambungan batang tarik baja hasil analisis kapasitas dan kegagalan sambungan seringkali memiliki nilai yang lebih rendah dari kapasitas sambungan dalam kondisi riil. Pada penelitian ini dilakukan perbandingan kapasitas sambungan batang tarik profil siku 30x30x3mm bermutu BJ-37 disambung dengan pelat mutu BJ-37 tebal 3mm dan baut penyambung diameter 8 mm dengan mutu A307 melalui studi analisis kapasitas dan kegagalan dan studi eksperimental dengan tipe kegagalan geser. Pada studi analisis kapasitas dan kegagalan sambungan batang tarik baja diperoleh kapasitas sambungan sebesar 18,9 kN dengan tipe kegagalan geser. Pada studi eksperimental dilakukan pengujian tarik sambungan baja batang tarik dengan 3 buah benda uji, didapatkan nilai rata-rata kapasitas ultimit sebesar 22,63 kN dan mengalami kegagalan geser baut pada ketiga benda uji. Kesimpulan yang dapat diambil dari penelitian ini adalah baik hasil perhitungan secara analitis dan pengujian eksperimental di laboratorium menunjukkan trend yang baik dan sama. Benda uji didesain berdasarkan perhitungan analitis untuk mengalami kegagalan geser pada baut, hasil pengujian eksperimental untuk 3 (tiga) benda uji seluruhnya menunjukkan pola kegagalan geser baut. Kekuatan nominal tarik rencana (Rn) dari hasil studi analitis dengan beban ultimit hasil studi eksperimental memiliki perbedaan sebesar 16,48 % dengan hasil eksperimental lebih tinggi. Melalui penelitian ini diharapkan dapat menjadi media pembelajaran untuk mengetahui salah satu jenis kegagalan pada sambungan batang tarik yaitu kegagalan geser baut, memperoleh gambaran perbandingan hasil perhitungan analtis yang mengacu pada standar perencanaan yang berlaku serta hasil pengujian eksperimental di laboratoriu

A microfabricated surface ion trap on a high-finesse optical mirror

A novel approach to optics integration in ion traps is demonstrated based on a surface electrode ion trap that is microfabricated on top of a dielectric mirror. Additional optical losses due to fabrication are found to be as low as 80 ppm for light at 422 nm. The integrated mirror is used to demonstrate light collection from, and imaging of, a single 88 Sr+ ion trapped $169\pm4 \mu$m above the mirror.Comment: 4 pages, 3 figure

Analysis of micromixers and biocidal coatings on water-treatment membranes to minimize biofouling.

Biofouling, the unwanted growth of biofilms on a surface, of water-treatment membranes negatively impacts in desalination and water treatment. With biofouling there is a decrease in permeate production, degradation of permeate water quality, and an increase in energy expenditure due to increased cross-flow pressure needed. To date, a universal successful and cost-effect method for controlling biofouling has not been implemented. The overall goal of the work described in this report was to use high-performance computing to direct polymer, material, and biological research to create the next generation of water-treatment membranes. Both physical (micromixers - UV-curable epoxy traces printed on the surface of a water-treatment membrane that promote chaotic mixing) and chemical (quaternary ammonium groups) modifications of the membranes for the purpose of increasing resistance to biofouling were evaluated. Creation of low-cost, efficient water-treatment membranes helps assure the availability of fresh water for human use, a growing need in both the U. S. and the world

Experimental Tests and Analytical Studies of Bearing-Type Axial Steel Connection

The capacity of the bolted connection on steel tensile rods can be determined through capacity analysis and connection failure. In term of capacity analysis and failure of steel tensile connection, the specified tensile connection capacity is generated based on several parameters such as cross-section of rod, grade of steel, thickness and grade of the steel plate, and grade and diameter of bolts. The capacity of steel tensile connections as a result of capacity analysis and connection failure often has a lower value than the connection capacity in real conditions. In this research, the comparison of 30x30x3mm angle cross-section connections with BJ37 grade quality was connected with 2 mm steel plate (also BJ37 grade) using 8 mm bolt connectors (A307 grade), through capacity analysis, failure study, and experimental study with type of failure is bolt bearing failure. In the capacity analysis study and the failure of steel tensile connections obtained a nominal capacity is 14.21 kN with the type of failure is shear failure. In the experimental study was tested 3 specimens, the average value of ultimate capacity was 18.67 kN and the failure for all of the three specimens are shear failures. The conclusion that can be drawn from this research is both the result of analytical calculations and experimental testing in the laboratory showed a good agreement and have the same trend. The test specimens were designed on the basis of analytical calculations for bolt bearing failure, experimental test results for all of three specimens all showed a failure pattern of bolt shear. The nominal strength from the results of the analytical study with the ultimate load of the experimental study results has a difference of 31.4% with higher experimental results. Through this research is expected to be a learning-media to know one type of failure on the steel connections that is bolt shear failure, obtain a comparison between analytical calculation results referring to applicable design standards, and the results of experimental testing in the laboratory