Coherent spin-spin coupling mediated by virtual microwave photons

We report the coherent coupling of two electron spins at a distance via virtual microwave photons. Each spin is trapped in a silicon double quantum dot at either end of a superconducting resonator, achieving spin-photon couplings up to around gs/2π = 40 MHz. As the two spins are brought into resonance with each other, but detuned from the...

Quantum-Classical Solution Methods for Binary Compressive Sensing Problems

Compressive sensing is a signal processing technique used to acquire and reconstruct sparse signals using significantly fewer measurement samples. Compressive sensing requires finding the most sparse solution to an underdetermined linear system, which is an NP-hard problem and as a consequence in practise is only solved approximately. In our...

NetSquid, a NETwork Simulator for QUantum Information using Discrete events

Quantum dot arrays in silicon and germanium

Electrons and holes confined in quantum dots define excellent building blocks for quantum emergence, simulation, and computation. Silicon and germanium are compatible with standard semiconductor manufacturing and contain stable isotopes with zero nuclear spin, thereby serving as excellent hosts for spins with long quantum coherence. Here, we...

Mathematical formulation of quantum circuit design problems in networks of quantum computers

Protecting quantum entanglement from leakage and qubit errors via repetitive parity measurements

Protecting quantum information from errors is essential for large-scale quantum computation. Quantum error correction (QEC) encodes information in entangled states of many qubits and performs parity measurements to identify errors without destroying the encoded information. However, traditional QEC cannot handle leakage from the qubit...

Rapid gate-based spin read-out in silicon using an on-chip resonator

Silicon spin qubits are one of the leading platforms for quantum computation1,2. As with any qubit implementation, a crucial requirement is the ability to measure individual quantum states rapidly and with high fidelity. Since the signal from a single electron spin is minute, the different spin states are converted to different charge states3,4....

Embedding silicon spin qubits in superconducting circuits

We demonstrate the strong coupling between a single electron spin in silicon and a single photon in a superconducting microwave cavity. Using the same cavity we perform rapid high-fidelity single-shot readout of two-electron spin states.

Entanglement between Nitrogen-Vacancy spin in diamond and Telecom frequency photon

We experimentally demonstrate the preservation of entanglement between an NV spin and a photon upon quantum frequency conversion to the Telecom band. This is a crucial step in realizing long-distance quantum networks.

An experimental microarchitecture for a superconducting qantum processor

Quantum computers promise to solve certain problems that are intractable for classical computers, such as factoring large numbers and simulating quantum systems. To date, research in quantum computer engineering has focused primarily at opposite ends of the required system stack: devising high-level programming languages and compilers to...

Thermo-mechanical challenges for quantum devices

In the last few years Technical University of Delft, under leadership of Prof.dr.ir. Leo Kouwenhoven, has developed several successful concepts for quantum devices that are suitable for quantum computing and quantum communication. From a quantum research point of view we are still in a very fundamental state, several practical issues already...