Delft – Kavli Institute Pre-Print Publications

Efficient Conversion of Optical to Mechanical States Close to the Single-Quantum Level

Posted by klaurent September 3, 2026Delft

Kavli Affiliate: Simon Groblacher | Summary:Coherent interfaces between optical photons and mechanical excitations provide a promising route towards phonon-state engineering and hybrid quantum information processing. Cavity optomechanical systems enable such interfaces via optomechanically induced transparency (OMIT), allowing coherent mapping between traveling optical fields and localized mechanical modes. However, previous implementations of OMIT conversion protocols were […]

Continue..

ScatterWorks: A Python package for building and solving scattering network models

Posted by klaurent August 28, 2026August 31, 2026Delft, This Week: Nanoscience

Kavli Affiliate: Anton Akhmerov | Summary:Network models provide an efficient framework for studying non-interacting transport and wave-propagation phenomena in disordered and topological systems. We introduce ScatterWorks, an open-source Python package for building and solving network models. The package uses a compact network representation with composable transformation operations (tile, cut, relink, and union) to enable flexible […]

Continue..

Band’s Geometry Origin of Quantum Spin Transport Phenomena

Posted by klaurent August 27, 2026August 31, 2026Delft, This Week: Nanoscience

Kavli Affiliate: Mazhar Ali | Summary: We develop a geometric description of spin-dependent transport based on the local geometric structure of electronic bands and the Fermi surfaces. For quasi-two-dimensional systems, we show that hyperbolic regions of constant-energy surfaces generate a geometrical contribution to the Fermi velocity that couples naturally to electron spin and produces a […]

Continue..

Light-Hole Spin Qubits in Strained SiGe Lattice-Matched to Ge

Posted by klaurent August 26, 2026August 31, 2026Delft, This Week: Nanoscience

Kavli Affiliate: Giordano Scappucci | Summary:Strained germanium ($varepsilon$-Ge) quantum wells on metamorphic SiGe buffers have enabled advanced hole-based spin qubit devices. Alternatively, unstrained Ge with lattice-matched strained silicon-germanium ($varepsilon$-SiGe) barriers eliminates the need for metamorphic buffers altogether. The ground state character of both these platforms is predominantly heavy-hole (HH) with a largely anisotropic spin response. […]

Continue..

Tools for Reducing Service Time in Near-Term Quantum Networks

Posted by klaurent August 21, 2026August 31, 2026Delft

Kavli Affiliate: Stephanie Wehner | Summary:Architectures have been proposed to control entanglement generation in multi-user quantum networks. To allow time for local operations and classical communication at end nodes, these architectures insert fixed separations between consecutive batches of entanglement generation attempts. This reduces network utilization when attempts fail, leaving the network idle during the scheduled […]

Continue..

Observation of magnetic quantum phase crossovers in a semiconductor spin ladder

Posted by klaurent August 18, 2026August 31, 2026Delft

Kavli Affiliate: Menno Veldhorst | Summary:Understanding collective phases of strongly correlated quantum magnets relies on theoretically tractable model systems with precise microscopic control. Antiferromagnetic spin ladders provide such a setting, hosting field-tunable gapped and gapless phases at half filling and unconventional pairing tendencies upon doping. Here, we realize a programmable Heisenberg spin ladder in a […]

Continue..

Monolithic high density integrated photonics on bulk lithium niobate

Posted by klaurent August 16, 2026Delft

Kavli Affiliate: Simon Groblacher | Summary:Functional electro-optic (EO) tunable photonic integrated circuits are crucial to next-generation information processing and advanced computing, where ferroelectric materials such as lithium niobate (LiNbO3) provide outstanding optical properties and versatile tuning mechanisms. However, beyond achieving high-performance devices, practical deployment of LiNbO3 photonic integrated circuits requires rapid and cost-effective scale-up, which […]

Continue..

Strain-controlled magnetism and magnetoelasticity in monolayer NiPS$_3$ and CrPS$_4$

Posted by klaurent August 11, 2026Delft

Kavli Affiliate: Herre Van Der Zant | Summary:We develop a first-principles framework for magnetoelastic coupling in two-dimensional magnets based on a strain-dependent Heisenberg model. In this approach, strain derivatives of the exchange interactions provide direct access to magnetostriction and to the magnetic renormalization of the elastic tensor, establishing a microscopic link between spin interactions and […]

Continue..

Assessing fidelity-limiting factors and achieving single-qubit gate fidelity beyond 99.999% in driven silicon spin qubits

Posted by klaurent August 11, 2026Delft

Kavli Affiliate: Giordano Scappucci | Summary:In semiconductor single-spin qubits, high-fidelity quantum gates have been demonstrated; however, achieving consistent performance remains challenging due to variations in driven qubit coherence, which is less explored than free-evolution coherence such as $T_2^*$. Here, we report single-qubit gate fidelities above 99.999%, achieved by dramatically extending the driven-spin coherence time and […]

Continue..

Buried germanium quantum well proximitised by magnetic field-resilient superconducting platinum iridium germanosilicide

Posted by klaurent August 10, 2026Delft

Kavli Affiliate: Giordano Scappucci | Summary:Hybrid superconductor-semiconductor systems provide a versatile platform for quantum technologies, ranging from superconducting-spin interfaces to topological quantum devices. Progress toward scalable implementations requires superconductors that exhibit high critical fields ($>1$T) at accessible temperatures integrated with low-disorder semiconductor heterostructures. Here we demonstrate a superconducting platinum iridium germanosilicide (PtIrSiGe), with critical out-of-plane […]

Continue..