# Deep and persistent spectral holes in Tm-doped yttrium orthosilicate for imaging applications

## TL;DR

This paper demonstrates deep, persistent spectral holes in Tm-doped YSO at cryogenic temperatures, highlighting its potential for medical imaging applications through advanced spectral hole burning techniques.

## Contribution

It reveals the potential of Tm:YSO for spectral filtering in medical imaging by demonstrating deep, persistent spectral holes under specific magnetic conditions.

## Key findings

- Deep, sub-MHz spectral holes achieved in Tm:YSO
- Spectral holes are persistent under cryogenic conditions
- Potential application in ultrasound optical tomography

## Abstract

With their optical wavelength in the near infrared (790-800nm) and their unique spectroscopic properties at cryogenic temperatures, thulium-doped crystals are at the center of many architectures linked to classical signal processing and quantum information. In this work, we focus on Tm-doped YSO, a compound that was left aside in the mid-1990s due to its rather short optical coherence lifetime. By means of time-resolved hole-burning spectroscopy, we investigate the anisotropic enhanced nuclear Zeeman effect and demonstrate deep, sub-MHz, persistent spectral hole burning under specific magnetic field orientation and magnitude. By estimating the experimental parameters corresponding to a real-scale ultrasound optical tomography setup using Tm:YSO as a spectral filter, we validate Tm:YSO as a promising compound for medical imaging in the human body.