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As a thermodynamic phase of matter, superconductors typically exist in an equilibrium state. But recently, researchers at JILA became interested in kicking these materials into excited states and exploring the ensuing dynamics. As reported in a new Nature paper, the theory and experiment teams of JILA and NIST Fellows Ana Maria Rey and James K. Thompson, in collaboration with Prof. Robert Lewis-Swan at the University of Oklahoma, simulated superconductivity under such excited conditions using an atom-cavity system.

In a new Optica paper, Ye’s team, working with JILA electronic staff member Ivan Ryger and John "Jan" Hall, describe implementing a new approach for the PDH method, reducing RAM to never-before-seen minimal levels while simultaneously making the system more robust and simpler.

NIST Fellow and University of Colorado Boulder Physics professor Jun Ye, in collaboration with JILA and NIST Fellow James K. Thompson, has used a specific process known as spin squeezing to generate quantum entanglement, resulting in an enhancement in clock performance operating at the 10-17stability level. Their novel experimental setup, published in Nature Physics, also allowed the researchers to directly compare two independent spin-squeezed ensembles to understand this level of precision in time measurement, a level never before reached with a spin-squeezed optical lattice clock.

In a new study published in Scientific Reports, JILA Fellow and University of Colorado Boulder physics professor Andreas Becker and his team theorized a new method to produce extreme ultraviolet (EUV) and x-ray light with elliptical polarization, a special shape in which the direction of light waves’ oscillation is changing. This method could provide experimentalists with a simple technique to generate such light, which is beneficial for physicists to further understand the interactions between electrons in materials on the quantum level, paving the way for designing better electronic devices such as circuit boards, solar panels, and more.

As reported in a new Science Advances paper, the JILA team and collaborators from universities in Sweden, Greece, and Germany probed the spin dynamics within a special material known as a Heusler compound: a mixture of metals that behaves like a single magnetic material. For this study, the researchers utilized a compound of cobalt, manganese, and gallium, which behaved as a conductor for electrons whose spins were aligned upwards and as an insulator for electrons whose spins were aligned downwards.

New research from JILA Fellow and University of Colorado Boulder physics professor Cindy Regal and her team, Dr. Ravid Shaniv and graduate student Chris Reetz has found that in specific scenarios, such as advanced studies looking at the interactions between light and mechanical objects, where the temperature might differ in various resonator parts, which lead to unexpected behaviors. Their observations, published in Physical Review Research, can potentially revolutionize the design of micro-mechanical resonators for quantum technology and precision sensing.

In quantum information science, many particles can act as “bits,” from individual atoms to photons. At JILA, researchers utilize these bits as “qubits,” storing and processing quantum 1s or 0s through a unique system.

While many JILA Fellows focus on qubits found in nature, such as atoms and ions, JILA Associate Fellow and University of Colorado Boulder Assistant Professor of Physics Shuo Sun is taking a different approach by using “artificial atoms,” or semiconducting nanocrystals with unique electronic properties. By exploiting the atomic dynamics inside fabricated diamond crystals, physicists like Sun can produce a new type of qubit, known as a “solid-state qubit,” or an artificial atom.

JILA Fellow Murray Holland and his research team proposed an algorithm that uses the Quantum Fisher Information Matrix (QFIM), a set of mathematical values that can determine the usefulness of entangled states in a complicated system.

Their results, published in Physical Review Letters as an Editor’s Suggestion, could offer significant benefits in developing the next generation of quantum sensors by acting as a type of “shortcut” to find the best measurements without needing a complicated model.

Recently graduated Ph.D. researchers Bin Wang and Nathan Brooks, working with JILA Fellows Margaret Murnane and Henry Kapteyn, developed a novel method that uses short-wavelength light with a special vortex or donut shape to scan these repeating surfaces, resulting in more varied diffraction patterns. This allowed the researchers to capture high-fidelity image reconstructions using this new approach, which they recently published in Optica.

Opening new possibilities for quantum sensors, atomic clocks and tests of fundamental physics, JILA researchers have developed new ways of “entangling” or interlinking the properties of large numbers of particles. In the process they have devised ways to measure large groups of atoms more accurately even in disruptive, noisy environments.

The new techniques are described in a pair of papers published in Nature. JILA is a joint institute of the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder.