Coherent states have been long known for their applications in quantum optics and atomic physics. In recent years, a number of new applications have emerged in the area of quantum information theory. In this talk I will highlight two such applications. The first is the comparison between classical and quantum strategies to process information. Byproducts of this comparison are benchmarks that can be used to certify quantum advantages in realistic experiments, fundamental relations between quantum copy machines and precision measurements, and theoretical tools for security proofs in quantum cryptography. The second application is the simulation of unitary gates in quantum networks. Here the task is to simulate a given set of unitary gates using gates in another set, a general problem that includes as special cases the simulation of charge conjugate dynamics and the emulation of an unknown unitary gate. The problem turns out to have useful connections with the ultimate precision limits of quantum metrology.[-]

Quantum information offers fundamentally new ways to achieve cryptographic tasks, sometimes beyond the capabilities of classical cryptography. In these two lectures, I will first introduce the important concepts in Quantum Information, and we will try to understand together how quantum communication enables new possibilities for cryptographic protocols. We will then explore quantum key distribution (QKD), the most well-known quantum cryptography protocol, understanding how it works and its security guarantees. I will also go beyond QKD to briefly discuss other cryptographic primitives where quantum cryptography has fundamental advantages and limitations, such as commitment or coin flipping. Finally, I will discuss emerging research directions in quantum communication that push the boundaries of secure information processing.[-]

Quantum information offers fundamentally new ways to achieve cryptographic tasks, sometimes beyond the capabilities of classical cryptography. In these two lectures, I will first introduce the important concepts in Quantum Information, and we will try to understand together how quantum communication enables new possibilities for cryptographic protocols. We will then explore quantum key distribution (QKD), the most well-known quantum cryptography protocol, understanding how it works and its security guarantees. I will also go beyond QKD to briefly discuss other cryptographic primitives where quantum cryptography has fundamental advantages and limitations, such as commitment or coin flipping. Finally, I will discuss emerging research directions in quantum communication that push the boundaries of secure information processing.[-]