Quantum limits in interferometric measurements

Quantum noise limits the sensitivity of interferometric measurements. It is generally admitted that it leads to an ultimate sensitivity, the ``standard quantum limit''. Using a semi-classical analysis of quantum noise, we show that a judicious use of squeezed states allows one in principle to push the sensitivity beyond this limit. This general method could be applied to large scale interferometers designed for gravitational wave detection.Comment: 4 page

Entangled and disentangled evolution for a single atom in a driven cavity

For an atom in an externally driven cavity, we show that special initial states lead to near-disentangled atom-field evolution, and superpositions of these can lead to near maximally-entangled states. Somewhat counterintutively, we find that (moderate) spontaneous emission in this system actually leads to a transient increase in entanglement beyond the steady-state value. We also show that a particular field correlation function could be used, in an experimental setting, to track the time evolution of this entanglement

Constraints for quantum logic arising from conservation laws and field fluctuations

We explore the connections between the constraints on the precision of quantum logical operations that arise from a conservation law, and those arising from quantum field fluctuations. We show that the conservation-law based constraints apply in a number of situations of experimental interest, such as Raman excitations, and atoms in free space interacting with the multimode vacuum. We also show that for these systems, and for states with a sufficiently large photon number, the conservation-law based constraint represents an ultimate limit closely related to the fluctuations in the quantum field phase.Comment: To appear in J. Opt. B: Quantum Semiclass. Opt., special issue on quantum contro

Can quantum chaos enhance stability of quantum computation?

We consider stability of a general quantum algorithm with respect to a fixed but unknown residual interaction between qubits, and show a surprising fact, namely that the average fidelity of quantum computation increases by decreasing average time correlation function of the perturbing operator in sequences of consecutive quantum gates. Our thinking is applied to the quantum Fourier transformation where an alternative 'less regular' quantum algorithm is devised which is qualitatively more robust against static random residual n-qubit interaction.Comment: 4 pages, 5 eps figures (3 color

Pembangunan Aplikasi Perhitungan Honor Dan Pengukuran Kinerja Asisten Praktikum Berbasis SaaS

Bagi suatu perguruan tinggi, kegiatan praktikum sangat penting untuk mendukung pembelajaran di kelas. Beberapa masalah yang muncul dalam pengelolaan kegiatan praktikum seperti keterlambatan pengumpulan berita acara praktikum (BAP) sehingga memperlambat perhitungan, pembayaran dan pelaporan honor asprak. Dibutuhkan waktu sekitar dua minggu untuk rekapitulasi dan validasi ratusan lembar BAP yang telah terkumpul setiap bulannya. Dibutuhkan pengolahan data lebih lanjut untuk menilai kinerja asprak berdasarkan data BAP. Untuk mengatasi permasalahan di atas maka dibangun aplikasi perhitungan honor dan kinerja asprak. Aplikasi ini digunakan untuk mengelola data BAP, perhitungan dan pelaporan honor, perhitungan nilai transkrip aktivitas kemahasiswaan (TAK) dan pencetakan sertifikat asprak. Keterbatasan SDM atau biaya menyebabkan tidak semua perguruan tinggi dapat langsung membuat aplikasi yang dibutuhkan. Oleh karena itu aplikasi ini dibangun berbasis Software as A Service (SaaS). Aplikasi ini dikembangkan dengan metode analisis perancangan terstruktur dengan model waterfall. Pengumpulan data kebutuhan aplikasi dilakukan dengan survey ke fakultas-fakultas di Universitas Telkom. Hasilnya dianalisis dan dikembangkan menjadi rancangan aplikasi. Aplikasi diimplementasikan pada pemrograman PHP. Pengujian dilakukan dengan metode black box testing. Hasilnya berupa aplikasi SaaS untuk perhitungan honor dan pengukuran kinerja asisten praktikum. Perguruan tinggi pengguna aplikasi SaaS ini dapat melakukan kostumisasi terhadap fitur yang ada sesuai dengan kebutuhan

Descriptive Analysis of Building Partnership Network in the Concept of Management Towards Non-Formal Educational Institution at Pkbm Ziona in 2023/2024

This research aimed to determine the concept of partnership management occured at PKBM Ziona with partner institutions. This research was descriptive research with a qualitative approach. The data source were the Head of PKBM Ziona and a staff member. Data collection techniques were observation, interviews and documentation with interview guide and documentation guide instruments. Data analysis used Miles and Huberman which includes data collection, data reduction, data presentation, as well as drawing conclusions and verification. The research results showed that: : 1). The process of partnership they did were mapping, digging and collecting information, analyzing information, cooperation exploration, making agreements, signing of Memorandum of Understanding (MOU), implementation of activities, monitoring and evaluation, improvement, and further planning; 2). The concept of partnership management they did in some  stages, namely (1) Partnership planning; (2) Implementation of the partnership includes realizing internal partnership activities industrial culture programs, as well as communication and coordination carried out by stakeholders who play a role; (3) Partnership evaluation includes monitoring and evaluation, reporting partnership activities, analysis of supporting factors and factors inhibiting partnerships include efforts to overcome obstacles, determination achievement of the objectives of partnership activities, benefits of partnerships, and development partnership. Both sides parties seek cooperation that is mutually helpful, complementary, and mutually beneficial. The collaboration that occurred has gone well and been successful

Dynamical localization simulated on a few qubits quantum computer

We show that a quantum computer operating with a small number of qubits can simulate the dynamical localization of classical chaos in a system described by the quantum sawtooth map model. The dynamics of the system is computed efficiently up to a time $t\geq \ell$, and then the localization length $\ell$ can be obtained with accuracy $\nu$ by means of order $1/\nu^2$ computer runs, followed by coarse grained projective measurements on the computational basis. We also show that in the presence of static imperfections a reliable computation of the localization length is possible without error correction up to an imperfection threshold which drops polynomially with the number of qubits.Comment: 8 pages, 8 figure