Dr Marco Piani



Personal statement

I joined the University in 2014 as Lecturer and Chancellor’s Fellow. My research deals with Quantum Information Processing, and focuses principally on the quantum properties of correlations exhibited by distributed quantum systems. My goals are those of deepening our understanding of quantum mechanics and facilitating the development of revolutionary quantum technologies. The latter go from unconditionally secure communications to improved measurement devices, to the efficient simulation of quantum systems, to incomparably faster computers. I am also interested in outreach and public engagement, in the belief that these activities are essential for the scientific literacy of the general population and to secure the public support to scientific research itself.


Local broadcasting of quantum correlations
Piani Marco
Lectures on General Quantum Correlations and their ApplicationsQuantum Science and Technology, (2017)
Hierarchy of efficiently computable and faithful lower bounds to quantum discord
Piani Marco
Phys. Rev. Lett. Vol 117, (2016)
Should entanglement measures be monogamous or faithful?
Lancien Cécilia, Di Martino Sara, Huber Marcus, Piani Marco, Adesso Gerardo, Winter Andreas
Phys. Rev. Lett. Vol 117, (2016)
Quantum reference frames associated with non-compact groups : the case of translations and boosts, and the role of mass
Smith Alexander R. H., Piani Marco, Mann Robert B.
Physical Review A Vol 94, (2016)
Robustness of coherence : an operational and observable measure of quantum coherence
Napoli Carmine, Bromley Thomas R., Cianciaruso Marco, Piani Marco, Johnston Nathaniel, Adesso Gerardo
Phys. Rev. Lett. Vol 116, (2016)
Robustness of asymmetry and coherence of quantum states
Piani Marco, Cianciaruso Marco, Bromley Thomas R., Napoli Carmine, Johnston Nathaniel, Adesso Gerardo
Physical Review A Vol 93, (2016)

more publications

Research interests

My research deals with Quantum Information Processing (QIP), and focuses principally on the quantum properties of correlations exhibited by distributed quantum systems.

The advent of Quantum Mechanics established a profound fracture in the way we describe and understand the world, revealing counterintuitive features of nature that still puzzle both the general public and the scientists. From a fundamental point of view, any aspect of quantum mechanics that cannot be accounted for in the realm of classical mechanics, that is, any sign of quantumness, is worth investigating in order to better understand quantum mechanics and nature itself. From a practical point of view, the history of science and technology - including, for example, the invention of the laser and the transistor — indicates that any quantum effect may be considered as having the potential to lead to disruptive technologies.

QIP is the result of the recognition that “Information is physical” (R. Landauer), combined with the fact that the basic laws of nature are quantum. This opens the opportunity to store and process information in ways that go beyond, for example, the standard — or, as typically referred to, classical — computers, based on a binary and exclusive logic. The extension of the theory of information and computation to the quantum case provides a number of promising applications, which range from a possible exponential speedup of quantum computers with respect to classical computers — e.g., in solving computational problems and efficiently simulating quantum systems — to secure cryptographic communication schemes. This has led to a huge effort, on both the theoretical and experimental sides, to “harness the quantum world”. At the core of the advantage of QIP over classical information processing lie quantum correlations, which are my main interest.

Quantum entanglement results when two or more quantum systems become so tightly intertwined that, in a sense, their shared properties dominate over their individual ones; for example, there can be at the same time perfect knowledge about a composite system and total uncertainty about its components. This can give rise to stronger-than-classical correlations between quantum systems, and indeed entanglement was already considered the most prominent quantum feature by one of the fathers of Quantum Mechanics, Erwin Shroedinger. Entanglement has proven to be a key resource in many QIP tasks; it allows, for example, quantum teleportation and quantum cryptography. It is then clear that the study of entanglement is both of practical and fundamental importance. The recent years have seen a growing interest in entanglement theory and many experiments nowadays aim at the generation, manipulation and use of entanglement. However, entanglement is not the whole story as, for example, quantum correlations need to be accessed and exploited by performing measurements. Based on the interplay between quantum states and local quantum measurements, the quantumness of correlations can thus assume stronger forms, like steering and nonlocality, for which entanglement is necessary but not sufficient, or weaker forms, like quantum discord, for which entanglement is sufficient but not necessary. Indeed, correlations can have quantum features even in the absence of entanglement, a fact recently linked to a potential quantum advantage in a number of QIP tasks even in the presence of a high level of noise.

In the above context, one may cast the relation between the foundational and applicative issues regarding quantum behavior in the following way:

Taking optimal advantage of quantum behavior requires the best possible understanding of it.

At the core of my research activity, which lies at the intersection of Mathematics, Physics and Information Theory, are the objectives of characterizing and exploiting the quantum properties of single and distributed systems. While I have often focused on the detection, generation and manipulation of entanglement, in the course of my career I have become more broadly interested in those physical effects that manifest the quantum features of nature. The unifying idea is that non-classicality is a very general property of single and multipartite systems, that goes beyond entanglement; at the same time entanglement is an extreme form of non-classicality that allows otherwise impossible effects, and as such it deserves special focus.

Professional activities

Robustness of resources and discrimination of physical processes
Conference on the Theory of Quantum Computation, Communication and Cryptography
Should entanglement measures be monogamous or faithful?
Resource robustness and discrimination of physical processes
University of Bristol
Visiting researcher
Resource robustness and discrimination of physical processes
Invited speaker

more professional activities


Doctoral Training Partnership (DTP 2016-2017 University of Strathclyde) | Tatsi, Gioan
Jeffers, John (Principal Investigator) Piani, Marco (Co-investigator) Tatsi, Gioan (Research Co-investigator)
Period 01-Oct-2016 - 01-Oct-2019
Doctoral Training Partnership (DTP 2016-2017 University of Strathclyde) | Surace, Jacopo
Piani, Marco (Principal Investigator) Tagliacozzo, Luca (Co-investigator) Surace, Jacopo (Research Co-investigator)
Period 01-Oct-2016 - 01-Apr-2020
EPSRC Doctoral Training Grant - DTA, University of Strathclyde | Lena, Rosaria Gabriella
Daley, Andrew (Principal Investigator) Piani, Marco (Co-investigator) Lena, Rosaria Gabriella (Research Co-investigator)
Period 01-Jan-2016 - 01-Jul-2019
Sentient observers in the quantum regime and the emergence of an objective reality
Piani, Marco (Principal Investigator)
Period 01-Feb-2017 - 31-Jul-2018
Operational Characterization of Quantum Correlations
Piani, Marco (Fellow) Daley, Andrew (Administrator)
Period 01-May-2015 - 01-May-2017

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