Storing and processing information using quantum two level systems (qubits) promises tremendous speed-up for certain computational tasks like prime factorisation and searching an unsorted database. In addition, many problems in quantum mechanics can also be solved a lot more efficiently. Scientist and engineers all over the world are trying to build the hardware that can implement these quantum algorithms. In this talk, I will present one particular approach which uses superconducting electrical circuits operating at millikelvin temperatures to implement the quantum hardware. I will introduce a new three-qubit device, nicknamed “trimon” [1], which is based on a multi-mode superconducting circuit providing strong inter-qubit coupling. I will discuss the basic working principles of the device, the implementation of efficient multi-qubit gates and the capability of universal programmability [2]. Next, I will demonstrate the high-fidelity preparation of various two- and three-qubit entangled states and realization of a few quantum algorithms like Deutsch-Jozsa, Grover etc [3]. I will end by talking about the possibility of scaling to larger systems using the trimon as a building block and the challenges ahead.

[1] Roy et al., Phys. Rev. Applied 7, 054025 (May 2017) 

[2] Roy at al., arXiv:1711.01658 (Nov 2017)

[3] Roy et al., arXiv:1809.00668 (Sep 2018)