Improving the Energy and Angular Resolutions of X-ray Telescopes with Nitrogen-Vacancy Centers in Diamond

TL;DR

This paper presents a novel detector design using nitrogen-vacancy centers in diamond integrated with a microcalorimeter array to significantly improve the energy and angular resolution of X-ray telescopes, enabling scalable, high-precision astronomical observations.

Contribution

The paper introduces a new NV-MMC detector architecture that allows simultaneous optical readout, enhancing resolution and scalability over existing sensor technologies.

Findings

Achieves ~0.17 arcsecond angular resolution

Attains ~0.70 eV energy resolution

Supports larger, finer arrays without additional cryogenic electronics

Abstract

We introduce a focal-plane detector for advancing the energy and angular resolutions of current X-ray telescopes. The architecture integrates a metallic magnetic microcalorimeter (MMC) array of paramagnetic absorber pads with a thin layer of nitrogen-vacancy (NV) centers in diamond for simultaneous optical readout. An impinging X-ray photon induces a temperature transient in an absorber pad, kept at ~35 mK. This time- and temperature-dependent magnetic field transient is then optically imaged by diamond NV centers, kept at 4 K and positioned directly below the pad. For a 10 $\mu$m absorber length used with a 12 m focal length telescope, our design yields an optimal angular resolution of ~0.17 arcseconds and energy resolution of ~0.70 eV. Our NV-MMC design improves upon current transition-edge sensors (TES) or MMCs read-out by superconducting quantum interference devices (SQUID) by enabling simultaneous optical readout of the entire MMC array. Because no additional cryogenic multiplexing electronics are required, our approach scales naturally to larger and finer arrays, supporting finer angular resolutions and wider fields of view.