225,622 research outputs found
Photonic quantum technologies
The first quantum technology, which harnesses uniquely quantum mechanical
effects for its core operation, has arrived in the form of commercially
available quantum key distribution systems that achieve enhanced security by
encoding information in photons such that information gained by an eavesdropper
can be detected. Anticipated future quantum technologies include large-scale
secure networks, enhanced measurement and lithography, and quantum information
processors, promising exponentially greater computation power for particular
tasks. Photonics is destined for a central role in such technologies owing to
the need for high-speed transmission and the outstanding low-noise properties
of photons. These technologies may use single photons or quantum states of
bright laser beams, or both, and will undoubtably apply and drive
state-of-the-art developments in photonics
From Quantum Optics to Quantum Technologies
Quantum optics is the study of the intrinsically quantum properties of light.
During the second part of the 20th century experimental and theoretical
progress developed together; nowadays quantum optics provides a testbed of many
fundamental aspects of quantum mechanics such as coherence and quantum
entanglement. Quantum optics helped trigger, both directly and indirectly, the
birth of quantum technologies, whose aim is to harness non-classical quantum
effects in applications from quantum key distribution to quantum computing.
Quantum light remains at the heart of many of the most promising and
potentially transformative quantum technologies. In this review, we celebrate
the work of Sir Peter Knight and present an overview of the development of
quantum optics and its impact on quantum technologies research. We describe the
core theoretical tools developed to express and study the quantum properties of
light, the key experimental approaches used to control, manipulate and measure
such properties and their application in quantum simulation, and quantum
computing.Comment: 20 pages, 3 figures, Accepted, Prog. Quant. Ele
Basic protocols in quantum reinforcement learning with superconducting circuits
Superconducting circuit technologies have recently achieved quantum protocols
involving closed feedback loops. Quantum artificial intelligence and quantum
machine learning are emerging fields inside quantum technologies which may
enable quantum devices to acquire information from the outer world and improve
themselves via a learning process. Here we propose the implementation of basic
protocols in quantum reinforcement learning, with superconducting circuits
employing feedback-loop control. We introduce diverse scenarios for
proof-of-principle experiments with state-of-the-art superconducting circuit
technologies and analyze their feasibility in presence of imperfections. The
field of quantum artificial intelligence implemented with superconducting
circuits paves the way for enhanced quantum control and quantum computation
protocols.Comment: Published versio
Reliable quantum certification for photonic quantum technologies
A major roadblock for large-scale photonic quantum technologies is the lack
of practical reliable certification tools. We introduce an experimentally
friendly - yet mathematically rigorous - certification test for experimental
preparations of arbitrary m-mode pure Gaussian states, pure non-Gaussian states
generated by linear-optical circuits with n-boson Fock-basis states as inputs,
and states of these two classes subsequently post-selected with local
measurements on ancillary modes. The protocol is efficient in m and the inverse
post-selection success probability for all Gaussian states and all mentioned
non-Gaussian states with constant n. We follow the mindset of an untrusted
prover, who prepares the state, and a skeptic certifier, with classical
computing and single-mode homodyne-detection capabilities only. No assumptions
are made on the type of noise or capabilities of the prover. Our technique
exploits an extremality-based fidelity bound whose estimation relies on
non-Gaussian state nullifiers, which we introduce on the way as a byproduct
result. The certification of many-mode photonic networks, as those used for
photonic quantum simulations, boson samplers, and quantum metrology, is now
within reach.Comment: 8 pages + 20 pages appendix, 2 figures, results generalized to
scenarios with post-selection, presentation improve
Quantum Technology: The Second Quantum Revolution
We are currently in the midst of a second quantum revolution. The first
quantum revolution gave us new rules that govern physical reality. The second
quantum revolution will take these rules and use them to develop new
technologies. In this review we discuss the principles upon which quantum
technology is based and the tools required to develop it. We discuss a number
of examples of research programs that could deliver quantum technologies in
coming decades including; quantum information technology, quantum
electromechanical systems, coherent quantum electronics, quantum optics and
coherent matter technology.Comment: 24 pages and 6 figure
Practical cryptographic strategies in the post-quantum era
We review new frontiers in information security technologies in
communications and distributed storage technologies with the use of classical,
quantum, hybrid classical-quantum, and post-quantum cryptography. We analyze
the current state-of-the-art, critical characteristics, development trends, and
limitations of these techniques for application in enterprise information
protection systems. An approach concerning the selection of practical
encryption technologies for enterprises with branched communication networks is
introduced.Comment: 5 pages, 2 figures; review pape
- …