The ability to process large amounts of information is one of the cornerstones of our digital society. Whether for predicting customer choices, optimizing commercial routes or managing financial risk, the efficient processing of information plays an increasingly relevant role in our economy. Furthermore, the upcomming of new technologies, like 5G or the Internet of Things, will boost the generation of new data. For those reasons, the enhancement of computational power is one of the main challenges faced by information technologies.

Quantum computing devices are one of the most promising candidates to address this challenge. Exploiting concepts such as quantum superposition, quantum computers can carry out certain tasks exponentially faster than conventional devices. This disruptive potential has been recogenized in the last years with a significant invesment from the public sector (US National Quantum Initiative Act, UK Quantum Hubs, European Flagship, amongst others), as well as from the private sector, where technological companies (Google, IBM and Microsoft) are actively pursuing the design and fabrication of quantum computers. Thanks to this joint effort, the first quantum information processors have evolved from a mere theoretical dream to a real technological tool which advances at an impressive pace every year. The first quantum computer prototypes are devices with up to 50 qubits, and some of them are available for remote access in the cloud.

Despite all this progress, quantum computation must address significant challenges before it becomes a disruptive technology. At the level of physical implementation (hardware), current state-of-the-art experimental platforms show scalability issuses due to limitations in size and operation speed. Furthermore, quantum error correction techniques demand extra resources that will most surely not be available in the near future. It is thus necessary to further developm quantum algorithms (software) that work even with imperfect, noisy hardware, such as the devices that can be currenlty fabricated.

In this collaborative project, we will combine the complementary expertise of the two participant research groups, experts in nanophotonics (UAM) and quantum technologies (CSIC), in a joint effort to address those challenges. On one hand, we will design quantum processors that rely on nanophotonic quantum systems, and which will allow to surpass size and operation speed limitations present in current systems. In particular, we will exploit the ability to confine light at the nanometer scale, and control its propagation, to couple qbits in a robust, fast and versitile manner. On the other hand, we will develop novel quantum computing paradigms that are adapted to this new photonic platform and which will allow us to address relevant practical problmes with current technology. For that aim we will design strategies to minimize the impact that the main sources of noise have on quantum algorithms. We will also investigate whether noise can even be exploited to enhance their performance.