How are lonely planets identified?

Planets outside the solar system are commonly called exoplanets. As they pass in front of their central star, the intensity of the star’s light decreases. We identify planets by seeing the dimming of that light. This is how most exoplanets are typically identified. But solitary planets cannot be identified in this way because they do not revolve around any particular star.
When a planet is newly formed it is extremely hot and cools slowly. During this cooling they emit infrared rays. And these infrared rays can be captured by microscopic cameras. However, lonely planets do not emit any kind of light, so they cannot be detected with infrared.
Scientists identify these planets through a process called ‘microlensing’. When an object with mass bends the surrounding space-time due to its mass, the phenomenon is called gravitational microlensing. When a planet is aligned with a distant star, the light emitted by the star is bent by the planet’s gravity as it approaches the planet. That is, this event indicates the possibility of there being a cosmic object. Researchers also determined the masses of solitary planets by looking at the position of the bent light. The shorter the period of microlensing, the lower the mass of the solitary planet.