A5086029476- Topological Materials and Phenomena
- Advanced Condensed Matter Physics
- Electronic and Structural Properties of Oxides
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum and electron transport phenomena
- Physics of Superconductivity and Magnetism
- Quantum optics and atomic interactions
- Atomic and Subatomic Physics Research
- Advanced Chemical Physics Studies
- Synthesis and Properties of Aromatic Compounds
- Lipid Membrane Structure and Behavior
- Catalytic Cross-Coupling Reactions
- Algebraic structures and combinatorial models
- Nonlinear Photonic Systems
- 3D Printing in Biomedical Research
- Magneto-Optical Properties and Applications
- Quantum many-body systems
- Analytical Chemistry and Sensors
- Graphene research and applications
- Opportunistic and Delay-Tolerant Networks
- Iron-based superconductors research
- Mobile Agent-Based Network Management
- Methane Hydrates and Related Phenomena
Delft University of Technology
2022-2025
QuTech
2022-2025
Leiden University
2024
Majorana bound states constitute one of the simplest examples emergent non-Abelian excitations in condensed matter physics. A toy model proposed by Kitaev shows that such can arise at ends a spinless $p$-wave superconducting chain. Practical proposals for its realization require coupling neighboring quantum dots chain via both electron tunneling and crossed Andreev reflection. While processes have been observed semiconducting nanowires carbon nanotubes, crossed-Andreev interaction was...
In most naturally occurring superconductors, electrons with opposite spins form Cooper pairs. This includes both conventional s-wave superconductors such as aluminium, well high-transition-temperature, d-wave superconductors. Materials intrinsic p-wave superconductivity, hosting pairs made of equal-spin electrons, have not been conclusively identified, nor synthesized, despite promising progress
The formation of a topological superconducting phase in quantum-dot--based Kitaev chain requires nearest neighbor crossed Andreev reflection and elastic cotunneling. Here, we report on hybrid InSb nanowire three-site geometry---the smallest system with well-defined bulk edge---where two superconductor-semiconductor hybrids separate three quantum dots. We demonstrate pairwise cotunneling between both pairs neighboring dots show sequential tunneling processes involving all These results are...
Quantum-dot-superconductor arrays have emerged as a new and promising material platform for realizing topological Kitaev chains. So far, experiments implemented two-site chain with limited protection. Here, we propose an experimentally feasible protocol scaling up the in order to enhance protection of Majorana zero modes. To this end, make use fact that relative sign normal superconducting hoppings mediated by Andreev bound state can be changed electrostatic gates. In way, our method only...
Abstract Cooper pairs occupy the ground state of superconductors and are typically composed maximally entangled electrons with opposite spin. In order to study spin entanglement properties these electrons, one must separate them spatially via a process known as pair splitting (CPS). Here we provide first demonstration CPS in semiconductor two-dimensional electron gas (2DEG). By coupling two quantum dots superconductor-semiconductor hybrid region achieve efficient splitting, clearly...
A short superconducting segment can couple attached quantum dots via elastic cotunneling (ECT) and crossed Andreev reflection (CAR). Such coupled host Majorana bound states provided that the ratio between CAR ECT be controlled. Metallic superconductors have so far been shown to mediate such tunneling phenomena, albeit with limited tunability. Here, we show formed in semiconductor-superconductor heterostructures over mesoscopic length scales. possess both an electron a hole component, giving...
Abstract Connecting double quantum dots via a semiconductor-superconductor hybrid segment offers platform for creating two-site Kitaev chain that hosts Majorana zero modes at finely tuned sweet spot. However, the effective couplings mediated by Andreev bound states in are generally weak tunneling regime. As consequence, excitation gap is limited size, presenting formidable challenge using this to demonstrate non-Abelian statistics and realize topological computing. Here we systematically...
Abstract Majorana zero modes are non-Abelian quasiparticles predicted to emerge at the edges of topological superconductors. A one-dimensional superconductor can be realized with Kitaev model—a chain spinless fermions coupled via p -wave superconductivity and electron hopping—which becomes in long-chain limit. Here we realize a three-site using semiconducting quantum dots by superconducting segments hybrid InSb/Al nanowire. We investigate robustness under varying coupling strengths...
In semiconducting-superconducting hybrid devices, Andreev bound states (ABSs) can mediate the coupling between quantum dots (QDs), allowing for realisation of artificial Kitaev chains. order to engineer Majorana (MBSs) in these systems, one must control energy ABSs. this work, we show how extended ABSs a flux tunable Josephson junction be used distant separated by $\approx$ 1 $\mathrm{\mu}$m. particular, demonstrate that combination electrostatic and phase over significantly increases...
The membrane curvature of cells and intracellular compartments continuously adapts to enable perform vital functions, from cell division signal trafficking. Understanding how geometry affects these processes
Cooper pairs occupy the ground state of typical s-wave superconductors and are composed maximally entangled electrons with opposite spin. In order to study spin entanglement properties these electrons, one must separate them spatially via a process known as pair splitting (CPS). Here we provide first demonstration CPS in semiconductor two-dimensional electron gas (2DEG). By coupling two quantum dots superconductor-semiconductor hybrid region achieve efficient splitting, clearly distinguish...
The formation of a topological superconducting phase in quantum-dot-based Kitaev chain requires nearest neighbor crossed Andreev reflection and elastic co-tunneling. Here we report on hybrid InSb nanowire three-site geometry - the smallest system with well-defined bulk edge where two superconductor-semiconductor hybrids separate three quantum dots. We demonstrate pairwise co-tunneling between both pairs neighboring dots show sequential tunneling processes involving all These results are next...
Contemporary quantum devices are reaching new limits in size and complexity, allowing for the experimental exploration of emergent modes. However, this increased complexity introduces significant challenges device tuning control. Here, we demonstrate autonomous Majorana zero modes a minimal realization Kitaev chain. We achieve task using cross-platform transfer learning. First, train model on theory model. Next, retrain it chain two-dimensional electron gas. Finally, apply to tune realized...
We theoretically explore the emergence of strong zero modes in a two-site chain consisting two quantum dots coupled due to central dot that mediates electron hopping and singlet superconducting pairing. In presence time-reversal symmetry, on-site Coulomb interaction leads three-fold ground-state degeneracy when tuning system sweet spot as function inter-dot couplings. This is protected against changes energies same way "poor man's'' Majorana bound states short Kitaev chains. limit...
A short superconducting segment can couple attached quantum dots via elastic co-tunneling (ECT) and crossed Andreev reflection (CAR). Such coupled host Majorana bound states provided that the ratio between CAR ECT be controlled. Metallic superconductors have so far been shown to mediate such tunneling phenomena, albeit with limited tunability. Here we show formed in semiconductor-superconductor heterostructures over mesoscopic length scales. possess both an electron a hole component, giving...
Artificial Kitaev chains can be used to engineer Majorana bound states (MBSs) in superconductor-semiconductor hybrids. In this work, we realize a two-site chain two-dimensional electron gas (2DEG) by coupling two quantum dots (QDs) through region proximitized superconductor. We demonstrate systematic control over inter-dot couplings in-plane rotations of the magnetic field and via electrostatic gating region. This allows us tune system sweet spots parameter space, where robust correlated...
Connecting double quantum dots via a semiconductor-superconductor hybrid segment offers platform for creating two-site Kitaev chain that hosts pair of "poor man's Majoranas" at finely tuned sweet spot. However, the effective couplings, which are mediated by Andreev bound states in hybrid, generally weak tunneling regime. As consequence, excitation gap is limited size, presenting formidable challenge using this to demonstrate non-Abelian statistics Majoranas and realizing error-resilient...
Quantum dot-superconductor arrays have emerged as a new and promising material platform for realizing Kitaev chains with Majorana zero modes. So far, experiments implemented two-site chain limited protection. We propose protocol scaling up the that is accessible to current optimizes To this end, we make use of fact relative sign normal superconducting hoppings mediated by an Andreev bound state can be changed electrostatic gates. In way, our method only relies on individual gates hybrid...
A chain of quantum dots (QDs) coupled via semiconductor-superconductor hybrid regions can form an artificial Kitaev hosting Majorana bound states (MBSs). These zero-energy are expected to be localised on the edges chain, at outermost QDs. The remaining QDs, comprising bulk, predicted host excitation gap that protects MBSs from local on-site perturbations. In this work, we demonstrate connection between bulk and in a minimal system, by engineering three-site two-dimensional electron gas....
Majorana bound states constitute one of the simplest examples emergent non-Abelian excitations in condensed matter physics. A toy model proposed by Kitaev shows that such can arise at ends a spinless $p$-wave superconducting chain. Practical proposals for its realization require coupling neighboring quantum dots chain via both electron tunneling and crossed Andreev reflection. While processes have been observed semiconducting nanowires carbon nanotubes, crossed-Andreev interaction was...
In most naturally occurring superconductors, electrons with opposite spins are paired up to form Cooper pairs. This includes both conventional $s$-wave superconductors such as aluminum well high-$T_\text{c}$, $d$-wave superconductors. Materials intrinsic $p$-wave superconductivity, hosting pairs made of equal-spin electrons, have not been conclusively identified, nor synthesized, despite promising progress. Instead, engineered platforms where brought into contact magnetic materials shown...
The membrane curvature of cells and intracellular compartments continuously adapts to enable perform vital functions, from cell division signal trafficking. Understanding how geometry affects these processes in vivo is challenging because the complexity as well short time small length scales involved. By contrast, vitro model membranes with engineered provide a versatile platform for this investigation applications biosensing biocomputing. However, general route fabrication lipid prescribed...