“Variational approach to photonic quantum circuits via the parameter shift rule”

In the current era of noisy intermediate-scale quantum computers, variational quantum algorithms represent one of the most viable approaches for their application to solve tasks of interest. These algorithms train a parameterized quantum circuit to execute a specific task encoded in a cost function that needs to be minimized using a classical optimizer. In this … Continua a leggere

“Modular Quantum-to-Quantum Bernoulli Factory in an Integrated Photonic Processor” just published in Nature Photonics

Generating and manipulating randomness is essential for numerous information technology applications, and quantum mechanics has been shown to offer distinct advantages in this area. A notable model for randomness manipulation is the Bernoulli factory, which enables the controlled adjustment of the bias in Bernoulli random processes. Initially, this framework was explored entirely within a classical … Continua a leggere

Quantum Lab at the European Researchers’ Night 2024

The Quantum Lab group of Sapienza University organized an engaging didactic exposition on quantum mechanics and quantum technologies titled “Dire l’indicibile” as part of the European Researcher’s Night 2024, held at Città dell’Altra Economia last weekend in Roma (link: https://www.scienzainsieme.it/). The event aimed to explore the fascinating and often counterintuitive world of quantum mechanics, making … Continua a leggere

“Polarization-encoded photonic quantum-to-quantum Bernoulli factory based on a quantum dot source” just published on Science Advances

A Bernoulli factory is a randomness manipulation routine that takes as input a Bernoulli random variable, outputting another Bernoulli variable whose bias is a function of the input bias. Recently proposed quantum-to-quantum Bernoulli factory schemes encode both input and output variables in qubit amplitudes. This primitive could be used as a subroutine for more complex … Continua a leggere

“Experimental verifiable multi-client blind quantum computing on a Qline architecture”

The exploitation of certification tools by end users represents a fundamentalaspect of the development of quantum technologies as the hardware scales upbeyond the regime of classical simulatability. Certifying quantum networksbecomes even more crucial when the privacy of their users is exposed tomalicious quantum nodes or servers as in the case of multi-client distributedblind quantum computing, … Continua a leggere

“Variational quantum cloning machine on a photonic integrated interferometer”

A seminal task in quantum information theory is to realize a device able to produce copies of a generic input state with the highest possible output fidelity, thus realizing an optimal quantum cloning machine. Recently, the concept of variational quantum cloning was introduced: a quantum machine learning algorithm through which, by exploiting a classical feedback … Continua a leggere

Two talks at the Optica Quantum 2.0, Rotterdam 26 June

Quantum 2.0 refers to the development and use of quantum superposition and entanglement in large engineered systems. Our faculty member Dr. Alessia Suprano and Dr. Beatrice Polacchi will participate with two talk contributions. Alessia Suprano talks about “”Photonic quantum extreme learning machine”, Beatrice Polacchi talks about “Multi-client blind quantum computing over a Qline architecture”. Link: … Continua a leggere

“Photonic implementation of quantum gravity simulator” published on Advanced Photonics Nexus

Detecting gravity-mediated entanglement can provide evidence that the gravitational field obeys quantum mechanics. We report the result of a simulation of the phenomenon using a photonic platform. The simulation tests the idea of probing the quantum nature of a variable by using it to mediate entanglement and yields theoretical and experimental insights, clarifying the operational … Continua a leggere

“High-fidelity four-photon GHZ states on chip” published on Quantum Information

Mutually entangled multi-photon states are at the heart of all-optical quantum technologies. While impressive progress has been reported in the generation of such quantum light states using free space apparatus, high-fidelity high-rate on-chip entanglement generation is crucial for future scalability. In this work, we use a bright quantum-dot based single-photon source to demonstrate the high … Continua a leggere