activity
20242026
collaborators

10 papers

quant-ph2026

Coherent Dark State Formation of a Lead-Vacancy Spin Qubit in Diamond

Yiyang Chen, Koyo Hirai, Tzyy Zheng Neo +7

A lead-vacancy (PbV) center in diamond exhibits coherent emission above the liquid helium temperature, making it highly attractive for quantum network applications. Here, we report…

quant-ph2026

Ten-Second Electron-Spin Coherence in Isotopically Engineered Diamond

Takashi Yamamoto, H. Benjamin van Ommen, Kai-Niklas Schymik +7

Solid-state spin defects are a promising platform for quantum networks. A key requirement is to combine long ground-state spin-coherence times with a coherent optical transition fo…

quant-ph2026

A Highly Sensitive Diamond NV Magnetometer Using Ramsey Interferometry with a Short Sensor-to-Sample Distance

Yuta Araki, Takeharu Sekiguchi, Yuji Hatano +11

In this study, we developed a diamond quantum magnetometer based on Ramsey interferometry with a short sensor-to-sample distance. Conventional biomagnetic sensors with ensemble nit…

quant-ph2025

Multichannel highly sensitive diamond quantum magnetometer

Atsumi Yoshimura, Ayumi Kanamoto, Naota Sekiguchi +9

We demonstrate a highly sensitive real-time magnetometry method at two measurement points. This magnetometry method is based on the frequency-division multiplexing of continuous-wa…

quant-ph2025

Optical charge state manipulation of lead-vacancy centers in diamond

Yiyang Chen, Yoshiyuki Miyamoto, Eiki Ota +5

Group-IV vacancy centers in diamond exhibit excellent optical and spin coherence properties, making them highly promising and scalable spin qubit candidates. Since only specific ch…

quant-ph2025

Current comparator for both AC and DC ratio measurements with 10-8-level accuracy

Hidekazu Muramatsu, Yuta Kainuma, Hiromitsu Kato +11

Accurate measurements of alternating current (AC) and direct current(DC) ratios are fundamental to electric power metrology. However, conventional current comparators for AC and DC…