- Name: Antonio Ortu
- Nationality: Italian
- Project: Rare-earth-ion doped quantum memories for quantum repeaters
- Host institution: Group of Applied Physics, University of Geneva
- Supervisor: Dr. Mikael Afzelius
I was born in the island of Sardinia, Italy, and grew up in a small village in a hilly countryside. In 2009, I obtained my high school degree of Technical Aviation Expert. I had my first experience abroad as AFS participant in 2007, thanks to which I lived for one year in Hudiksvall, Sweden, where I attended a local high school and lived with a local family.
I started my studies in physics at University of Pisa, Italy, where I obtained both my Bachelor (2014) and Master degrees (2016), and which included an experience of one year with the Erasmus+ program at KU Leuven, in Belgium. In Pisa, I worked on my thesis in a cavity optomechanics experiment, under the supervision of Prof. Donatella Ciampini. In 2017 I joined the quantum memory and repeaters project lead by Mikael Afzelius at the Group of Applied Physics at University of Geneva, Switzerland, and hence the QCALL network, as a PhD student.
I am interested on all aspects of quantum physics in general, especially by its “weirdness” and counterintuitive predictions, while at the same time I love how we can learn to use it in our everyday lives. In front of a beer, I will probably draw you down in conversations about technology, foreign cultures and languages and, of course, physics!
We can think of a quantum network as a group of nodes where quantum information can be processed. For these nodes to communicate, light can be used as a carrier of qubits and optical fibers-based connections will direct photons from the sender to the receiver. However, losses are inevitable, and increasingly so on long distances. This has consequences on the overall performance on the network as low communication rates. A possible solution to this problem is the use of quantum repeaters.
A simple implementation relies on the creation of pairs of entangled photons which will travel to the nodes we want to connect from a repeater, after which a measurement will confirm the successful sharing of entanglement.
At this level, quantum memories come into play. The generated entangled photons can be stored in order to wait for all the nodes to be connected by entanglement. This dramatically increases the rate of communication among nodes.
In my project at QCALL, I work on a practical implementation of a quantum memory. More specifically, I am investigating the quantum properties of solid state materials doped with Rare Earth ions, which are able to “store” the state of an input photon as a collective excitation of their internal degrees of freedom and release it on demand as an output photon.