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"Bidang ilmu superkonduktivitas telah lama menarik perhatian para peneliti. Penelitian terkait pengaplikasian material superkonduktor pun telah banyak dilakukan. Melalui penelitian ini, telah dipelajari pengaruh dua perlakuan panas berbeda terhadap pembentukan pelet BaPb1-xBixO3 (BPBO) melalui reaksi padatan dengan komposisi x = 0; 0,05; dan 0,25. Telah dipelajari juga potensi fabrikasi kawat superkonduktor BaPb0,75Bi0,25O3 menggunakan dua metode, yaitu powder-in-tube (PIT) in-situ dan ex-situ. Hasil karakterisasi X-Ray Diffraction (XRD) menunjukkan bahwa sampel yang dibentuk melalui perlakuan panas kedua memiliki ketunggalan fasa yang lebih baik dengan jumlah fasa pengotor yang lebih sedikit. Parameter kisi dan fasa yang terbentuk, serta perhitungan ukuran crystallite dengan metode Scherrer dan Williamson-Hall Plot telah berhasil dilakukan. Peningkatan unsur Bi pada BPBO terbukti menurunkan ukuran crystallite sampel. Karakterisasi Scanning Electron Microscopy (SEM) kemudian dilakukan untuk mempelajari struktur dan morfologi permukaan, homogenitas, ukuran grain, serta porositas yang terbentuk pada sampel pelet dan kawat BPBO. Pengujian resistivitas terhadap temperatur kemudian dilakukan menggunakan Cryogenic Magnetometer. Hasil pengujian mengklarifikasi munculnya fasa superkonduktor pada pelet BaPb0,95Bi0,05O3 (perlakuan panas kedua) dengan nilai Tc onset = 11,5 K dan Tc zero = 5,3 K dan BaPb0,75Bi0,25O3 (perlakuan panas pertama) dengan nilai Tc onset = 11,1 K dan Tc zero = 4 K.

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The field of superconductivity has long piqued the interest of researchers. Numerous studies have been carried out to explore the application of superconducting materials. Through this research, the effect of two heat treatments in the making of BaPb1-xBixO3 (BPBO) pellets using solid state reaction method with a composition of x = 0; 0,05; 0,25 has been studied. The fabrication potential of BaPb0,75Bi0,25O3-based superconducting wire using two different methods, powder-in-tube (PIT) in-situ and ex-situ, has also been studied. The result of X-Ray Diffraction (XRD) shows pellet samples that underwent the second heat treatment have better phases with fewer impurity peaks. The lattice parameters, phases, and the calculation of crystallite size using Scherrer method and Williamson-Hall Plot method have also been calculated. The increase of Bi concentration in BPBO proved to lower the crystallite sizes. Scanning Electron Microscopy (SEM) is used to study the structure and morphology, homogeneity, grain sizes, and porosity of the samples. The resistivity behavior has also been studied using Cryogenic Magnetometer. Superconducting states can be found in pellet samples of BaPb0,95Bi0,05O3 (second heat treatment) with Tc onset = 11,5 K and Tc zero = 5,3 K, and BaPb0,75Bi0,25O3 (first heat treatment) with Tc onset = 11,1 K and Tc zero = 4 K."

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Observabel dari \f{topological defect} di alam semesta dapat diperlajari dengan menyelidiki ruang-waktunya. Konsekuensi paling jelas dari ruang-waktu untuk pendeteksi objek tersebut adalah pelensaan gravitasi. Salah satu dari tipe \f{topological defect} yang paling mungkin untuk ada adalah dawai kosmik. Tensi/tegangan dalam dawai dapat disetimbangkan dengan adanya arus mengalir di dalamnya, memungkinkan terbentuknya \f{loop} stabil yang dinamakan vorton. Keberadaan objek-objek ini diprediksi dalam model terra Witten $U(1)\times U(1)$ dan teori elektrolemah $SU(2)\times U(1)$. Dalam studi ini, ruang-waktu dari \f{loop} dawai kosmik superkonduktor ditelaah, dimulai dari solusi metrik dari vorton \f{chiral} lingkaran, efek pelensaan gravitasinya, dan gambar terlensakan dari beberapa keluarga solusi vorton \f{chiral} menggunakan pendekatan lensa tipis. Kita juga menganalisis dinamika dari \f{loop} dawai superkonduktor dalam latar ruang-waktu Kerr-Newman.

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Observables of topological defects in the universe can be studied by examining its spacetime. The most obvious properties of spacetime for the detection of such objects would be the gravitational lensing. One of the likely type of topological defect to exist is the cosmic string. The tension of the string could be balanced by a current flowing inside it, possibly forming a stable loop called vorton. The existence of these objects is predicted both in the Witten gauge $U(1)\times U(1)$ model and electroweak $SU(2)\times U(1)$ theory. In this study, the spacetime of superconducting string loop is examined, starting from the metric solution of a circular chiral vorton, its gravitational lensing effect, and the lensing image of various families of chiral vorton solutions using the thin lens approximation. We also analyze the dynamics of superconducting string loop in the Kerr-Newman spacetime background.

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"This thesis presents a novel method for fabricating the smallest superconducting quantum interference device (SQUID) that resides on the apex of a very sharp tip. The nanoSQUID-on-tip displays a characteristic size down to 100 nm and a field sensitivity of 10^-3 Gauss/Hz^(1/2). A scanning SQUID microsope was constructed by gluing the nanoSQUID-on-tip to a quartz tuning-fork. This enabled the nanoSQUID to be scanned within nanometers of the sample surface, providing simultaneous images of sample topography and the magnetic field distribution. This microscope represents a significant improvement over the existing scanning SQUID techniques and is expected to be able to image the spin of a single electron."

"High-temperature superconducting (HTS) materials are becoming more and more attractive in the context of designing RF/microwave filters because of their lower losses and excellent performance. This book focuses on the superconducting microwave filter and its application in modern communication. It first presents the basic principles, HTS materials and processing and then introduces several types of multi-band HTS bandpass filter (BPF), discussing their properties and analyzing equivalent circuit models and their performances. This book is a valuable resource for students and researchers who are interested in wireless communication and RF/microwave design."