Solid-state lasers are a type of laser that use a solid material as the gain medium to produce light. This gain medium is typically a crystal or glass that is doped with specific ions, such as neodymium or yttrium. When energy is applied to the medium, it excites the ions, causing them to emit photons, which are then amplified to create a coherent beam of light. These lasers are known for their efficiency and durability, making them suitable for various applications, including medical procedures, industrial cutting, and scientific research. Solid-state lasers can produce different wavelengths of light, allowing for versatility in their use across multiple fields.