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Néel temperature, often referred to as TN, is a critical temperature point below which a material ceases to be a permanent magnet and enters a paramagnetic or a ferrimagnetic state. Named after Louis Néel, the French physicist who first described the phenomenon, this temperature varies depending on the material in question.

Above the Néel temperature, magnetic moments in the material can flip freely, resulting in the loss of spontaneous magnetization. The specific temperature value for a given material can range from a few Kelvin to several hundred degrees Celsius. If a substance is ferromagnetic, it typically has a well-defined singleTN, whereas antiferromagnetic materials may exhibit a range of TN values depending on the particular magnetic ordering.

As magnetic properties are crucial in various technological applications, controlling the Néel temperature becomes important for designing magnetic materials software and equipment. For example, in information storage devices, the individual layers in a thin-film magnetic recording head are carefully selected to operate at or above the material's TN. Advanced magnetic technologies benefit from a detailed understanding of the Néel temperature in both experimental and theoretical investigations.