# Two-qubit logic between distant spins in silicon

**Authors:** Jurgen Dijkema, Xiao Xue, Patrick Harvey-Collard, Maximilian Rimbach-Russ, Sander L. de Snoo, Guoji Zheng, Amir Sammak, Giordano Scappucci, Lieven M. K. Vandersypen  
**arXiv:** [2310.16805](https://arxiv.org/abs/2310.16805)  
**Date:** 2023-10-25  
**Summary page:** https://www.summarizepaper.com/en/paper/2310.16805v1/

## Key points

- Researchers investigate interaction between quantum particles and importance of utilizing different length scales for future qubit architectures
- Focus on interaction between two semiconductor spin qubits 250 µm apart, larger than commonly used direct interaction mechanisms
- Utilize superconducting resonator as mediator for coherent spin-spin coupling through virtual photons
- Observations show anti-phase oscillations of populations of two spins with controllable frequency
- Consistent with iSWAP oscillations and ten nanosecond entangling operations
- Findings hold promise for scalable networks of spin qubit modules on a chip in quantum computing technologies
- Highlights importance of exploring different interaction mechanisms on various length scales to enhance qubit architectures
- Opens up new possibilities for building more advanced quantum systems by allowing for coherent interactions between distant spin qubits using a superconducting resonator

## Summary

In this study, the researchers investigate the interaction between quantum particles and the importance of utilizing different length scales for future qubit architectures. They specifically focus on the interaction between two semiconductor spin qubits that are 250 µm apart, which is significantly larger than the commonly used direct interaction mechanisms in this platform. To facilitate this interaction, they utilize a superconducting resonator to act as a mediator for a coherent spin-spin coupling through virtual photons. By operating the system in this regime, they are able to observe anti-phase oscillations of the populations of the two spins with controllable frequency. The observations made in this study are consistent with iSWAP oscillations and ten nanosecond entangling operations. These findings hold promise for scalable networks of spin qubit modules on a chip, which could have significant implications for future quantum computing technologies. This research highlights the importance of exploring different interaction mechanisms on various length scales to enhance qubit architectures and opens up new possibilities for building more advanced quantum systems by allowing for coherent interactions between distant spin qubits using a superconducting resonator.