Sökning: "Quantum Gate"

Visar resultat 1 - 5 av 73 avhandlingar innehållade orden Quantum Gate.

1. 1. Machine learning for quantum information and computing

   Författare :Shahnawaz Ahmed; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; quantum machine learning; quantum process tomography; quantum information; Machine learning; generative neural networks; variational quantum algorithms; quantum state tomography; optimization; quantum computing; Bayesian estimation;

   Sammanfattning : This compilation thesis explores the merger of machine learning, quantum information, and computing. Inspired by the successes of neural networks and gradient-based learning, the thesis explores how such ideas can be adapted to tackle complex problems that arise during the modeling and control of quantum systems, such as quantum tomography with noisy data or optimizing quantum operations, by incorporating physics-based constraints. LÄS MER

3. 2. Controllable coupling of superconducting qubits and implementation of quantum gate protocols

   Författare :Margareta Wallquist; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Controllable Qubit-Coupling; Single Cooper-Pair Box; Josephson Effect; Quantum Gate; Superconducting Circuit; Quantum Computer; Qubit; Quantum Electrical Circuit;

   Sammanfattning : The concept of a quantum computer was invented in the beginning of the 1980s as a quantum generalization of the reversible classical computer. After discoveries in the middle of the 1990s of quantum algorithms, which wouldsolve some problems considered intractable for classical computers, the field of quantum computing has developed rapidly. LÄS MER

4. 3. Quantum and Ballistic Nanodevices

   Författare :Ivan Shorubalko; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; III-V semiconductors; low-dimensional structures; nanostructures; ballistic rectifiers; three-terminal ballistic junctions; quantum wires; planar quantum dots; logic gates; harmonic generation; InP; GaInAs; nanoelectronics; Fysik; Physics; nonlinear transport; electron transport; quantum nanodevices; ballistic nanodevices; Fysicumarkivet A:2003:Shorubalko;

   Sammanfattning : In this thesis, electron transport in quantum and ballistic devices was studied. The devices studied here were quantum wires, planar quantum dots, ballistic rectifiers, artificial functional materials, and three-terminal ballistic junctions. The possible application of such devices in the future nanoelectronics was also investigated. LÄS MER

5. 4. Modelling of Quantum Transport in Nanostructures

   Författare :Dan Csontos; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ballistic transport; quantum wire; quantum dot; resonant tunnelling; three-terminal; disorder; Physics; Fysik; Fysicumarkivet A:2002:Csontos; scattering matrix; quantum transport;

   Sammanfattning : In this thesis, theoretical studies of the transport properties of three nanoscale systems: one-dimensional (1D) quantum wires (QWRs), zero-dimensional (0D), laterally confined, double-barrier resonant tunnelling structures (DBRTSs) and three-terminal ballistic junctions (TBJs), have been performed. In the first part of the thesis, an overview of the realization and properties of such systems is given along with a description of modelling tools used in the calculations. LÄS MER

7. 5. Resonant Tunneling in Laterally Confined Quantum Structures

   Författare :Boel Gustafson; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; gravitation; relativity; quantum mechanics; classical mechanics; Mathematical and general theoretical physics; Fysik; Physics; High peak-to-valley ratio; Lateral confinement; Quantum dots; Resonant tunneling; Self-assembled quantum dots; Schottky depletion; Buried metal gate; Electron transport; Magnetic-field dependence; Energy level width; Tunneling transistors; Mode coupling; statistical physics; thermodynamics; Matematisk och allmän teoretisk fysik; klassisk mekanik; kvantmekanik; relativitet; statistisk fysik; termodynamik; Technological sciences; Teknik; Fysicumarkivet A:2001:Gustafson;

   Sammanfattning : In the thesis, three-dimensionally confined resonant tunneling structures were studied experimentally. Two approaches were used for obtaining quantum confinement: gate-defined lateral constriction of double barrier structures, and epitaxial growth of self-assembled quantum dots. LÄS MER