Coherent States

Using single photons as qubits has become a prominent strategy in quantum information technology. Accurately determining the number of photons is crucial in various quantum systems, including quantum computation, quantum communication, and quantum metrology.

Semiconducting perovskites that exhibit superfluorescence at room temperature do so due to built-in thermal 'shock absorbers' which protect dipoles within the material from thermal interference.

Semiconducting perovskites that exhibit superfluorescence at room temperature do so due to built-in thermal "shock absorbers" which protect dipoles within the material from thermal interference. A new study from North Carolina State University explores the mechanism involved in this macroscopic quantum phase transition and explains how and why materials like perovskites exhibit macroscopic quantum coherence at high…

Physicists at the University of Innsbruck have succeeded in creating hot Schrödinger cat states in a superconducting microwave resonator.

Today, we are excited to launch Borealis, a new quantum processing unit (QPU) on Amazon Braket. Borealis – a special-purpose QPU built by Xanadu – is the first publicly available quantum computer with a claim to quantum computational advantage (sometimes referred to as quantum supremacy or quantum advantage) in a peer-reviewed study. With this launch, […]

Why this technology could have a big impact on EV charging times.

By using quantum key distribution (QKD), quantum cryptographers can share information via theoretic secure keys between remote peers through physics-based protocols. The laws of quantum physics dictate that photons carrying signals cannot be amplified or relayed through classical optical methods to maintain quantum security. The resulting transmission loss of the channel can limit its achievable distance to form a…

What plagues quantum upscaling? Most quantum computing devices are dependent on using complex physical phenomena that are either very short-lived (~10-12 seconds) and/or only survive at ultra-low temperatures (e.g., 10-3 to 10-6 Kelvin) and/or require ultra-high vacuum environments, except possibly those using nitrogen vacancy centers in diamonds or color centers in silicon, silicon carbide, etc.

An innovative new technique to detect and characterize molecules with greater precision has been proposed, paving the way for significant advances in environmental monitoring, medical diagnostics, and industrial processes.

We have demonstrated how to correct one of the two kinds of errors that cripple quantum computers

The field of experimental quantum communication promises ways of efficient and unconditional secure information exchange in quantum states. The possibility of transferring quantum information forms a cornerstone of the emerging field of quantum communication and quantum computation. Recent breakthroughs in quantum computation with superconducting circuits trigger a demand for quantum communication channels between…

Non-perturbative interactions (i.e., interactions too strong to be described by so-called perturbation theory) between light and matter have been the topic of numerous research studies. Yet the role that quantum properties of light play in these interactions and the phenomena arising from them have so far remained widely unexplored.

The pursuit of superconductivity at 400K has turned the scientific community and laypeople alike into a whirlpool of excitement, skepticism, and curiosity. Once deemed a distant dream, a series of…

In a recent study published in Physical Review Letters, a research team led by Prof. Guo Guangcan from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) achieved on-demand storage of photonic qubits at telecom wavelengths using a laser-written waveguide fabricated in an erbium-doped crystal.

(Phys.org)—Quantum coherence and quantum entanglement are two landmark features of quantum physics, and now physicists have demonstrated that the two phenomena are "operationally equivalent"—that is, equivalent for all practical purposes, though still conceptually distinct. This finding allows physicists to apply decades of research on entanglement to the more fundamental but less-well-researched concept of…

For the first time, researchers have successfully generated strongly nonclassical light using a modular waveguide-based light source. The achievement represents a crucial step toward creating faster and more practical optical quantum computers.