# Near-Field Scanning Microwave Microscopy in the Single Photon Regime

## TL;DR

This paper presents a cryogenic near-field scanning microwave microscope capable of operating at the single microwave photon level, enabling quantum-scale investigations of nano-structures for quantum technology applications.

## Contribution

It introduces a low-power NSMM that maintains dielectric contrast at the single-photon level, advancing quantum-compatible microwave microscopy.

## Key findings

- Achieved nano-scale dielectric contrast at single microwave photon regime
- Operates at power levels up to 10^9 times lower than typical NSMMs
- Discussed challenges for quantum coherent interactions with two-level systems

## Abstract

The microwave properties of nano-scale structures are important in a wide variety of applications in quantum technology. Here we describe a low-power cryogenic near-field scanning microwave microscope (NSMM) which maintains nano-scale dielectric contrast down to the single microwave photon regime, up to $10^{9}$ times lower power than in typical NSMMs. We discuss the remaining challenges towards developing nano-scale NSMM for quantum coherent interaction with two-level systems as an enabling tool for the development of quantum technologies in the microwave regime.