Kavli Affiliate: Michael Wimmer | Summary:This review is devoted to the different techniques that have been developed to compute the phase-coherent transport properties of quantum nanoelectronic systems connected to electrodes. Beside a review of the different algorithms proposed in the literature, we provide a comprehensive and pedagogical derivation of the two formalisms on which these […]
Kavli Affiliate: Toeno Van Der Sar | Summary:Fiber-coupled sensors are well suited for sensing and microscopy in hard-to-reach environments such as biological or cryogenic systems. We demonstrate fiber-based magnetic imaging based on nitrogen-vacancy (NV) sensor spins at the tip of a fiber-coupled diamond nanobeam. We incorporated angled ion implantation into the nanobeam fabrication process to […]
Kavli Affiliate: Andrea D. Caviglia | Summary:Quantum materials are characterized by electromagnetic responses intrinsically linked to the geometry and topology of electronic wavefunctions, encoded in the quantum metric and Berry curvature. Whereas Berry curvature-mediated transport effects have been identified in several magnetic and nonmagnetic systems, quantum metric-induced transport phenomena remain limited to topological antiferromagnets. Here […]
Kavli Affiliate: Michael Wimmer | First 5 Authors: Chun-Xiao Liu, Sebastian Miles, Alberto Bordin, Sebastiaan L. D. ten Haaf, Grzegorz P. Mazur | Summary: Quantum dot-superconductor arrays have emerged as a new and promising material platform for realizing topological Kitaev chains. So far, experiments have implemented a two-site chain with limited protection. Here we propose […]
Kavli Affiliate: Michael Wimmer | First 5 Authors: Chun-Xiao Liu, Sebastian Miles, Alberto Bordin, Sebastiaan L. D. ten Haaf, Grzegorz P. Mazur | Summary: Quantum dot-superconductor arrays have emerged as a new and promising material platform for realizing topological Kitaev chains. So far, experiments have implemented a two-site chain with limited protection. Here we propose […]
Kavli Affiliate: Sander Otte | Summary:Scaling magnets down to where quantum size effects become prominent triggers quantum tunneling of magnetization (QTM), profoundly influencing magnetization dynamics. Measuring magnetization switching in an Fe atomic chain under a carefully tuned transverse magnetic field, we observe a non-monotonic variation of magnetization lifetimes around a level crossing, known as the […]
Kavli Affiliate: P. G. Steeneken | Summary:Most microphones operate by detecting the sound-pressure induced motion of a membrane. In contrast, here we introduce a microphone that operates by monitoring the sound-pressure-induced modulation of the compressibility of air. By driving a graphene membrane at its resonance frequency, the gas, that is trapped in a squeeze-film beneath […]
Kavli Affiliate: Wolfgang Tittel | Summary:Rare-earth ion-doped crystals are of great interest for quantum memories, a central component in future quantum repeaters. To assess the promise of 1$%$ Tm$^3+$-doped yttrium gallium garnet (Tm:YGG), we report measurements of optical coherence and energy-level lifetimes of its $^3$H$_6$ $leftrightarrow$ $^3$H$_4$ transition at a temperature of around 500 mK […]
Kavli Affiliate: Tim H. Taminiau | Summary:Nuclear quadrupolar resonance (NQR) spectroscopy reveals chemical bonding patterns in materials and molecules through the unique coupling between nuclear spins and local fields. However, traditional NQR techniques require macroscopic ensembles of nuclei to yield a detectable signal, which precludes the study of individual molecules and obscures molecule-to-molecule variations due […]
Kavli Affiliate: Mazhar Ali | Summary: We have reexamined the moments of positive maps and the criterion based on these moments to detect entanglement. For two qubits, we observed that reduction map is equivalent to partial transpose map as the resulting matrices have the same set of eigenvalues although both matrices look different in same […]