What is thulium used for?
By RareMetals.net Editorial Team · Updated
Thulium is used mainly in thulium fibre lasers for surgery, especially for breaking up kidney stones, and as thulium-170 in portable X-ray sources. It is also used in optical amplifiers and in research materials. Because it is the scarcest stable rare earth, its uses are small and specialised.
Main uses of thulium at a glance
| Application | What thulium does | Examples |
|---|---|---|
| Surgical lasers | Thulium fibre lasers emit around 1.94 µm, strongly absorbed by water | Kidney-stone treatment, prostate surgery |
| Portable X-ray sources | Thulium-170 emits low-energy X-rays without electricity | Field radiography, industrial inspection |
| Optical amplifiers | Thulium-doped fibre amplifies wavelengths erbium does not cover | Telecommunications research |
| Research | Magnetic and superconducting materials | Laboratory materials science |
Thulium lasers in medicine
Thulium-doped fibre lasers emit infrared light at about 1.94 µm, a wavelength water absorbs very strongly. That lets surgeons vaporise or cut tissue with little damage below the surface. Urologists use them to break up kidney and bladder stones and to remove enlarged prostate tissue; they compete with holmium lasers and can produce finer stone dust.
Solid-state thulium:YAG lasers (about 2.0 µm) are used in similar procedures and in some soft-tissue surgery.
Portable X-ray sources
Irradiating natural thulium-169 in a reactor makes thulium-170, which emits low-energy X-rays and has a half-life of about 128 days. Sealed thulium-170 sources can take radiographs without electricity, for field medicine, dental imaging and industrial inspection. The USGS lists portable X-rays among the main uses of heavy rare earths.
Optical amplifiers and lasers
Thulium-doped fibre amplifies light in bands that erbium does not cover, including the telecom S-band and the 2 µm region. Eye-safe 2 µm thulium lasers are also used for processing plastics and in some sensing and lidar research.
Research materials
Thulium compounds are studied in magnetic materials, ceramics and high-temperature superconductors, but these uses are small.
Products that contain thulium
- Surgical lasers for kidney stones and prostate surgery
- Portable X-ray units
- Fibre amplifiers and 2 µm industrial lasers
Can thulium be replaced?
Holmium lasers compete directly with thulium lasers in urology. X-ray tubes or other isotopes can replace thulium-170 sources wherever power is available.
Thulium uses FAQ
What is thulium used for in medicine?
Thulium fibre lasers treat kidney and bladder stones and enlarged prostates, and thulium-170 is used in portable X-ray sources.
Is a thulium laser better than a holmium laser?
They suit slightly different jobs. Thulium fibre lasers can break stones into finer dust and are compact; holmium lasers have a longer track record. The choice is a clinical one for the surgeon.
Why is thulium so rarely used?
It is the least abundant stable rare earth (about 0.5 ppm of the crust) and expensive to separate, so it is used only where its properties are hard to replace.