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[ES] La computación cuántica es un área de investigación que estudia los algoritmos y sistemas que usan las propiedades de la física cuántica para solucionar problemas matemáticos complejos o costosos. La principal ventaja de los computadores cuánticos es la capacidad de los cúbits de mantener una superposición de ambos estados {0,1}. Gracias a esto, se consigue evaluar y guardar todas las posibles soluciones simultáneamente cuya consecuencia es una mejora exponencial al obtener los resultados. El trabajo consiste en desarrollar un simulador de computación cuántica que permite ejecutar circuitos cuánticos con varias puertas lógicas y varios cúbits en un ordenador clásico. La aplicación del simulador es de escritorio, está acompañada de una interfaz gráfica, desarrollada con el lenguaje Python y tiene un carácter educativo, ilustrando los fenómenos de la cuántica. Puedes simular tus propios circuitos arrastrando las puertas lógicas, guardarlos en el ordenador o lanzarlos en hardware cuántico real de proveedores como IBM. Se comparan las características de los distintos sistemas cuánticos actuales de importantes empresas tecnológicas., [EN] Quantum computing is an area of research that studies algorithms and systems that use the properties of quantum physics to solve complex or hard mathematical problems. The main advantage of quantum computers is the ability of qubits to maintain a superposition of both {0,1} states. Thanks to this, it is possible to evaluate and store all possible solutions simultaneously, the consequence of which is an exponential improvement in obtaining the results. The work consists of developing a quantum computing simulator that allows running quantum circuits with several logic gates and several qubits on a classical computer. The desktop application of the simulator is accompanied by a graphical interface, developed with the Python language and has a teaching approach, illustrating the phenomena of quantum. You can simulate your own circuits by dragging the logic gates, save them in the computer or launch them on real quantum hardware from providers such as IBM. It compares the characteristics of different current quantum systems from major technology companies., [CA] La computació quàntica és un àrea d’investigació que estudia els algorismes i sistemes que usen les propietats de la física cuàntica per a solucionar problemes matemàtics complexos o costosos. El principal avantatge dels computadors quàntics és la capacitat dels qubits de mantindre una superposición de tots dos estats {0,1}. Gràcies a això, s’aconsegueix avaluar i guardar totes les possibles solucions simultàniament que dona com a consequència una millora exponencial en l’obtenció dels resultats. El treball consisteix a desenvolupar un simulador de computació quàntica que permet executar circuits quàntics amb diverses portes lògiques i diversos qubits en un ordinador clàssic. L’aplicació del simulador és d’escriptori, està acompanyada d’una interfície gràfica, desenvolupada amb el llenguatge Python i té un caràcter educatiu, il·lustrant els fenòmens de la quàntica. Pots simular els teus propis circuits arrossegant les portes lògiques, guardar-los en l’ordinador o llançar-los en maquinari quàntic real de proveïdors com IBM. Es comparen les característiques dels diferents sistemes quàntics actuals d’importants empreses tecnològiques.

Booleove funkcije i S-kutijeˇcesto se koriste kao kriptografske primitive. Krip-tografske primitive moraju pokazivati odre ̄dena matematiˇcka svojstva kako bi moglaodoljevati napadima. Generiranje kriptografski signifikatnih Booleovih funkcija i S-kutija je složen i zahtjevan posao koji se pokušava riješiti principima kvatnog raˇcunar-stva. Osim generiranja kvatno se raˇcunarstvo može koristiti i za ispitivanje svojstavate samo implementaciju primitiva. Boolean functions and S-boxes are often used as cryptographic primitives. Cryp-tographic primitives must show certain mathematical properties in order to withstandattacks. Generating cryptographically significant Boolean functions and S-boxes isa complex and demanding job that is being solved with the principles of quantumcomputing. In addition to generating, quantum computing can also be used to testproperties and implement primitives.

In the past few years, IBM has expanded their Quantum Experience to include a high-level Python module called Qiskit as well as a 15-qubit machine (ibmq_16_melbourne). In order to evaluate IBM’s progress, we create an overview of the processes involved in developing and running an algorithm on IBM’s quantum machines. This includes exploring the new resources that IBM has made available recently including the Qiskit Python module. Then, we test textbook algorithms such as the Deutsch-Jozsa algorithm, Grover’s search algorithm, and Quantum Fourier Transform on ibmq_16_melbourne and compare the results with the output of a simulator. Constraints imposed by IBM’s Quantum Experience and significant differences between algorithm performance on IBM's quantum hardware and the simulator will be used to assess IBM’s quantum computing capabilities. Ensign, United States Navy Approved for public release. distribution is unlimited

The goal of this research report was to draw the state of the art of the advancement in quantum computing as part of a project of the International Master Research of the ISIMA engineering school. To do so, we first studied the principles of quantum physics required to understand quantum computing, namely, quantum superposition, quantum entanglement and wave-function collapse. These principles define a qubit which represents thequantum information. Qubits are, however, limited by decoherence, which prevents them to stay in a superposed state for a long period of time, and the no-cloning theorem, which prevents the copy of the superposed state of a qubit. We can interact with qubits thanks to quantum gates which composed quantum circuits. Throughout this project, we analysed Grover’s algorithm which is a quantum search algorithm. Then, we implemented it with Qiskit, a Python’s library developed by IBM. Eventually, we executed it on a real quantum computer available on IBM Q Experience and we found reproducibility issues. Today, quantum computers cannot handle many qubits nor apply many quantum gates, but it was enough for Google to claim to have reached quantum supremacy in October 2019.; Le but de ce rapport de recherche était de dresser un état de l’art de l’avancement en informatique quantique dans le cadre d’un projet du Master de recherche international de l’école d’ingénieur ISIMA. Pour cela, nous avons d’abord étudié les principes de la physique quantique nécessaires à la compréhension de l’informatique quantique, à savoir, la superposition quantique, l’intrication quantique et la réduction du paquet d’onde. Ces principes permettent de définir le concept de qubit qui est le support de l’information quantique. Le qubit est limité par le phénomène de décohérence qui empêche les qubits de rester longtemps dans un état superposé. De plus, il est impossible de copier l’état d’un qubit à cause du théorème de non-clonage. Les qubits peuvent être manipulés avec des portes quantiques qui forment alors des circuits quantiques.Au cours de ce projet, nous avons analysé l’algorithme de Grover qui est un algorithme quantique de recherche. Puis, nous l’avons implémenté à l’aide de la bibliothèque Python Qiskit développée par IBM. Enfin, nous avons exécuté cet algorithme sur un véritable ordinateur quantique mis à disposition via la plateforme IBM Q Experience et nous avons constaté des problèmes de reproductibilité.A ce jour, les ordinateurs quantiques ne sont capables de manipuler qu’un nombre restreint de qubits et de leurs appliquer un nombre restreint de portes quantiques mais cela a été suffisant pour que Google affirme avoir atteint la suprématie quantique en octobre 2019.